[PATCH] gcc: configure: Fix the optimization flags cleanup

[PATCH] gcc: configure: Fix the optimization flags cleanup

Currently sed command in flag cleanup removes all the -O[0-9] flags, ignoring
the context. This leads to issues when the optimization flags is passed to
linker:

CFLAGS="-Os -Wl,-O1 -Wl,--hash-style=gnu"
is converted into
CFLAGS="-Os -Wl,-Wl,--hash-style=gnu"

Which leads to configure failure with ld: unrecognized option '-Wl,-Wl'.

gcc/
	* configure.ac: Only remove -O[0-9] if not preceded with comma
	* configure: Regenerated