re PR target/50447 ([avr] Better support of AND, OR, XOR and PLUS with constant integers for 16- and 32-bit values)

	PR target/50447
	PR target/50465
	* config/avr/avr-protos.h (avr_out_bitop): New prototype.
	(avr_popcount_each_byte): New prototype.
	* config/avr/avr.c (avr_popcount): New static function.
	(avr_popcount_each_byte): New function.
	(avr_out_bitop): New function.
	(adjust_insn_length): ADJUST_LEN_OUT_BITOP dispatches to
	avr_out_bitop.  Cleanup code.
	* config/avr/constraints.md (Ca2, Co2, Cx2): New constraints.
	(Ca4, Co4, Cx4): New constraints.
	* config/avr/avr.md (adjust_len): Add "out_bitop" insn attribute
	alternative.
	(andhi3, iorhi3, xorhi3): Rewrite insns using avr_out_bitop.
	(andsi3, iorsi3, xorsi3): Ditto.
	(*iorhi3_clobber, *iorsi3_clobber): Remove insns.

From-SVN: r179081