arm64: make member of struct pt_regs and it's offset macro in the same order

arm64: make member of struct pt_regs and it's offset macro in the same order

In struct pt_regs, member pstate is after member pc. Move offset macro
of pstate after offset macro of pc to improve readability a little.

Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20240130175504.106364-1-shikemeng@huaweicloud.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>