arm64: Sort vendor-specific errata

Sort configuration options for vendor-specific errata by vendor, to
increase uniformity.
Move ARM64_WORKAROUND_REPEAT_TLBI up, as it is also selected by
ARM64_ERRATUM_1286807.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Will Deacon <will@kernel.org>