re PR target/57506 ([avr] Some devices are present twice in avr-mcus.def)

re PR target/57506 ([avr] Some devices are present twice in avr-mcus.def)

	PR target/57506
	* config/avr/avr-mcus.def (atmega16hva, atmega16hva2, atmega16hvb)
	(atmega16m1, atmega16u4, atmega32a, atmega32c1, atmega32hvb)
	(atmega32m1, atmega32u4, atmega32u6, atmega64c1, atmega64m1):
	Remove duplicate devices.
	* config/avr/gen-avr-mmcu-texi.c (print_mcus): Fail on duplicate MCUs.
	* config/avr/t-multilib: Regenerate.
	* config/avr/avr-tables.opt: Regenerate.
	* doc/avr-mmcu.texi: Regenerate.

From-SVN: r200870