Various Ada RTS files failed -fcompare-debug compilation because debug
stmts prevented EH cleanups from taking place.  Adjusting
cleanup_empty_eh to skip them fixes it.

for  gcc/ChangeLog

	* gimple-iterator.h (gsi_one_nondebug_before_end_p): New.
	* tree-eh.c (cleanup_empty_eh): Skip more debug stmts.

From-SVN: r244088