Update bindgen requirement from 0.53.0 to 0.55.1

[dependabot-preview]

Updates the requirements on bindgen to permit the latest version.

Changelog

Sourced from bindgen's changelog.

0.55.1

Released 2020/08/24.

Fixed

• Fixed a regression where anonymous enums referenced by members or such won't generate valid Rust code. (#1882).

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0.55.0

Released 2020/08/23.

Removed

• Support for libclang 3.8 has been removed (#1830).

Added

• Added options to avoid deriving the Debug trait (#1858).

• Added options to allow to override the default anonymous field prefix (#1859).

• Added options to allow to override the default macro integer type from the command line (#1863).

Changed

• Typed anonymous enums now generate better code (#1850).

• Objective-C bindings are more idiomatic now (#1847).

• Updated to clang-sys 1.0. Minimum supported rust version is 1.40 as a consequence of that change.

Fixed

• Fixed constness of multi-dimensional arrays in some cases (#1861).

• Fixed wrong target given to clang when compiling with a target which doesn't match the target clang expects (#1870, #1878).

• Fixed wrong flags being computed for cross-compilation cases where the target wasn't explicitly provided via clang flags (#1872).

Thanks again to all the awesome contributors that sent patches included in this release!

Commits

• d492ac4 v0.55.1
• 428189c tests: Improve enum tests to avoid duplication, and add a test for #1880
• bef180d codegen: Do generate unnamed enums, as they can be referred to by members.
• 0996486 Release v0.55.0
• f4d0b7c lib: Fix inferred target when clang target differs from rust target.
• 6653d0c Document that 0.54.1 has been yanked.
• 704b9ee Update to clang-sys 1.0.0
• c153553 Bump MSRV to 1.40.0
• 18ed6f4 codegen: Simplify a bit the code in #1847
• 4299255 Added Bindgen names to objective-c pointer return types
• Additional commits viewable in compare view

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[dependabot-preview]

Superseded by #22.