Patch is adding 'cortex-a510' to -mcpu command line option.

gcc/ChangeLog:

2021-09-02  Przemyslaw Wirkus  <przemyslaw.wirkus@arm.com>

	* config/aarch64/aarch64-cores.def (AARCH64_CORE): New
	Cortex-A510 core.
	* config/aarch64/aarch64-tune.md: Regenerate.
	* doc/invoke.texi: Update docs.