PR c/3190
	PR c/8714
	* c-format.c (set_Wformat): Do not enable -Wformat-y2k by default.
	* invoke.texi: Update.

testsuite:
	PR c/3190
	PR c/8714
	* gcc.dg/format/c90-strftime-1.c, gcc.dg/format/c90-strftime-2.c,
	gcc.dg/format/c99-strftime-1.c, gcc.dg/format/ext3.c,
	gcc.dg/format/no-y2k-1.c: Update.

From-SVN: r73378