[Ada] Casing style on record components

[Ada] Casing style on record components

This patch fixes a bug where the -gnatyr switch fails to detect
incorrect casing of record components.

gcc/ada/

	* style.adb (Check_Identifier): Deal with the case where a
	record component definition has been transformed; we want to
	warn if the original came from source.
	* libgnat/s-objrea.ads, libgnat/s-objrea.adb: Fix casing of MF
	to be consistent.
	* uname.adb: Fix casing of Chars to be consistent.
	* sem_util.ads: Minor comment fix.