Refactor C API

[edubart]

This is the actual implementation of the new C API overhaul. This is mostly finished and ready for review.

Added:

• Added command line options for serializing machine config as JSON (--load-json-config and --store-json-config).
• Lua API: Added new tojson/fromjson/tobase64/frombase64 functions.
• Added support for VirtIO devices in JSON configs.
• Added new method for receiving CMIO requests.

Changed:

• The headers *-defines.h are not installed anymore (they are now considered implementation details which external people should not care about, try to depend on or bind).
• Changed compiler for flags sanitize=yes and debug=yes to improve backtrace and catch more bugs.
• Help and configs are now printed to stdout instead of stderr.
• Simplified how Lua configs are serialized in cartesi-machine.lua, impacting its ordering.
• All processor CSRs, x, f and uarch registers were grouped together into a single register enumeration.
• Some Lua API functions have changed to reflect the new C API.
• The CSRs htif.tohost/htif.fromhost promoted reason to be an official 2-bytes field, its data field shrunk to 4 bytes.
• Changed sibling hashes ordering in JSON logs to match the expected ordering in the Lua test suite.
• Changed jsonrpc API to reflect the new API changes, bumping its version to 0.0.2.
• Bootargs changed to auto detect root flash drive filesystem (it will mount ext2 using ext4 driver).
• Include default bootargs in the default machine config.
• Flash drive start address configuration is non mandatory anymore (it will be automatically chosen).
• Changed fork method of remote machines to also return the process pid.
• Changed rebind method of remote machines to support binding on port 0 and return the bound address.
• Proofs are now mandatory in access logs.
• Disabled Sv57 virtual address translation mode from the RISC-V interpreter.
• Omitted no4lvl from bootargs, it's not needed anymore.

Removed:

• Removed dkjson Lua library (not needed since we have our own JSON encoding functions now).
• Removed clua-htif.cpp (its constants are exposed along with other Lua constants now).
• Removed GDB documentation from the repository (it was moved to the wiki).
• Removed many dead code after the refactoring.
• Removed machine-c-defines.h header (its constants are now gone or in the machine C API header).

C API Added:

• Added cm_get_last_error_message, returning the error message for the most recent failed call.
• Added public PMA enums with CMIO and RAM memory addresses.
• Added cm_constant enumeration with new constants.
• Added cm_cmio_yield_command and cm_cmio_yield_reason` enumeration with CMIO yields.
• Added cm_access_log_type enumeration with bitwise flags for access log type.
• Added cm_pma_constant enumeration.
• Added CM_REG_* for all machine control registers.
• Added CM_MCYCLE_MAX macro and set to UINT64_MAX
• Added register views for HTIF fromhost/tohost DEV/CMD/REASON/DATA fields.
• Added register views for IFLAGS PRV/X/Y/H fields.
• Added new API cm_receive_cmio_request to make it easier to perform IO using CMIO protocol.

C API Removed:

• Removed all err_msg arguments (the latest error message can be retrieved from cm_get_last_error_message()).
• Removed all one_based arguments from log related functions (its error messages now use user ordinal numbers).
• Removed machine runtime config arguments from verify functions (they were unused).
• Removed cm_new_default_machine_config
• Removed cm_get_f_address
• Removed cm_get_x_address
• Removed cm_reset_iflags_X/cm_set_iflags_H/cm_set_iflags_X
• Removed cm_verify_*_log.
• Removed all structs, complex data structures are passed as JSON strings now.
• Removed all cm_read_*/cm_write_* of all registers, except for mcycle/uarch_cycle/uarch_halt_flag/iflags.
• Removed most cm_delete_* functions.
• Removed some CM_ERROR_* enums.

C API Renamed:

• Renamed cm_read_csr -> cm_read_reg
• Renamed cm_write_csr -> cm_write_reg
• Renamed cm_get_csr_address -> cm_get_reg_address
• Renamed cm_create_machine -> cm_create
• Renamed cm_load_machine -> cm_load
• Renamed cm_delete_machine -> cm_destroy
• Renamed *_uarch_reset* -> *_reset_uarch*
• Renamed *_uarch_step* -> *_step_uarch*
• Renamed cm_verify_*_state_transition -> cm_verify_*
• Renamed cm_machine_run -> cm_run
• Renamed cm_machine_run_uarch -> cm_run_uarch
• Renamed CM_PROC_CSR -> CM_REG
• Renamed cm_create_jsonrpc_machine -> cm_jsonrpc_create_machine
• Renamed cm_load_jsonrpc_machine -> cm_jsonrpc_load_machine
• Renamed cm_get_jsonrpc_machine -> cm_jsonrpc_get_machine
• Renamed cm_create_jsonrpc_mgr -> cm_jsonrpc_create_mgr
• Renamed cm_delete_jsonrpc_mgr -> cm_jsonrpc_destroy_mgr
• Renamed all enum types to use lowercase letters.

C API Changed:

• Changed all C API functions to always return an error code and set last error message.
• Changed all C API functions to always set output values, even on failure.
• Enhanced generic read/write CSRs API to also support x, f and uarch registers.
• Changed cm_replace_memory_range to take multiple arguments instead of a struct.
• Changed cm_get_default_config output to its return instead of parameter (because it should never fail in practice).
• Changed cm_get_memory_ranges to output a JSON string instead of a struct.
• All functions now use only integers with fixed size (to simplify C binding generators).
• Reorganized the C API into different categories in the header (making it easy for the reader to navigate through the API).
• Changed error enumerations to use negative integers (to please rust bindgen).
• Access log types are now defined by bitwise flags instead of a structure (for the remove structs goal).
• Replaced all definitions with enums (because they are more friendly for binding generators).
• Polished the C API documentation.