arm64: cputype: Add Cortex-X925 definitions

Add cputype definitions for Cortex-X925. These will be used for errata
detection in subsequent patches.

These values can be found in Table A-285 ("MIDR_EL1 bit descriptions")
in issue 0001-05 of the Cortex-X925 TRM, which can be found at:

  https://developer.arm.com/documentation/102807/0001/?lang=en



Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20240603111812.1514101-4-mark.rutland@arm.com


Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>