Conditionally Set KLAYOUT_VERSION Based on KLAYOUT_CMD

[ivysochyn]

Conditionally Set KLAYOUT_VERSION Based on KLAYOUT_CMD

This PR updates the flow/Makefile to conditionally set the KLAYOUT_VERSION variable only if KLAYOUT_CMD is set. This change ensures that the KLAYOUT_VERSION assignment is performed safely and only when KLAYOUT_CMD is defined, preventing potential errors when KLAYOUT_CMD is not set. These errors usually result in noisy logs, but they don't crash the build.

An example error typically observed during the synth stage:

bash: - : invalid option
Usage:  bash [GNU long option] [option] ...
    bash [GNU long option] [option] script-file ...
GNU long options:
    --debug
    --debugger
    --dump-po-strings
    --dump-strings
    --help
    --init-file
    --login
    --noediting
    --noprofile
    --norc
    --posix
    --pretty-print
    --rcfile
    --restricted
    --verbose
    --version
Shell options:
    -ilrsD or -c command or -O shopt_option     (invocation only)
    -abefhkmnptuvxBCHP or -o option

This PR modifies the following:

• flow/Makefile - Updates the assignment of KLAYOUT_VERSION to use the $(if ...) function to check if KLAYOUT_CMD is set before executing the shell command. Also, fixes typos.

[oharboe]

Tested. Works now.

Before:

$ make KLAYOUT_CMD= print-KLAYOUT_VERSION
bash: - : invalid option
Usage:	bash [GNU long option] [option] ...
	bash [GNU long option] [option] script-file ...
GNU long options:
	--debug
	--debugger
	--dump-po-strings
	--dump-strings
	--help
	--init-file
	--login
	--noediting
	--noprofile
	--norc
	--posix
	--pretty-print
	--rcfile
	--restricted
	--verbose
	--version
Shell options:
	-ilrsD or -c command or -O shopt_option		(invocation only)
	-abefhkmnptuvxBCEHPT or -o option
KLAYOUT_VERSION = 
$

After:

$ make KLAYOUT_CMD= print-KLAYOUT_VERSION
KLAYOUT_VERSION = 
$