PR target/52737
	* contrib/gcc_update (files_and_dependencies):
	Remove gcc/config/avr/t-multilib from touch data.

gcc/
	PR target/52737
	* config.gcc (tm_file): Remove avr/multilib.h.

	* doc/invoke.texi (AVR Options): Adjust
	documentation of -mtiny-stack.

	* config/avr/genmultilib.awk: Remove code to generate multilib.h.
	(BEGIN): Use -msp8 as multilib option instead of -mtiny-stack.
	* config/avr/t-avr: Remove generation of multilib.h.
	* config/avr/t-multilib: Regenerate.
	* config/avr/multilib.h: Remove.
	* config/avr/avr.opt (-msp8): New option.
	(avr_sp8): New variable.
	* config/avr/driver-avr.c (avr_device_to_sp8): New function.
	* config/avr/avr.h (AVR_HAVE_SPH): New define.
	(AVR_HAVE_8BIT_SP): Also set by avr_sp8 i.e. -msp8.
	(avr_device_to_sp8): New prototype.
	(EXTRA_SPEC_FUNCTIONS): Add { "device_to_sp8", avr_device_to_sp8 }
	(DRIVER_SELF_SPECS): New define.
	* config/avr/avr-c.c (avr_cpu_cpp_builtins): New built-in defines:
	__AVR_SP8__, __AVR_HAVE_SPH__.
	* config/avr/avr.c (output_movhi): Use AVR_HAVE_SPH instead of
	AVR_HAVE_8BIT_SP to decide if SP_H is present.
	(avr_file_start): Ditto.
	
libgcc/
	PR target/52737
	* config/avr/lib1funcs.S: Use __AVR_HAVE_SPH__ for SP_H checks
	instead of __AVR_HAVE_8BIT_SP__.

From-SVN: r185907