re PR debug/53740 (--enable-checking=yes,rtl bootstrap failure with ada)

gcc/
	PR debug/53740
	* df.h (dead_debug_add): Remove third argument.
	* df-problems.c (dead_debug_add): Likewise.  Use the REGNO of the
	REG that we want to replace instead.
	(dead_debug_insert_temp): Use the REGNO of the reg that we want
	to replace instead of DF_REF_REGNO.  Require there to always be
	at least one such use.  Check for cases where the same location
	has more than df_ref associated with it.
	(df_note_bb_compute): Remove third dead_debug_add argument.
	* dce.c (word_dce_process_block): Likewise.

From-SVN: r188934