cfgcleanup.c: Include rtl-iter.h.

cfgcleanup.c: Include rtl-iter.h.

gcc/
	* cfgcleanup.c: Include rtl-iter.h.
	(mentions_nonequal_regs): Turn from being a for_each_rtx callback
	to being a function that examines each subrtx itself.
	(thread_jump): Update accordingly.

From-SVN: r214626