* Makefile.in.in: Take --defines switch off of xgettext

	command line.
	* POTFILES.in: Massive update, removing all dead files and
	adding approximately 300 files which had been left out.
	Clarify comments on what should and should not appear here.

	* gcc.pot: Regenerate.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@43228 138bc75d-0d04-0410-961f-82ee72b054a4