arm64: perf: Consistently make all event numbers as 16-bits

Arm ARM documents PMU event numbers as 16-bits in the table and more 0x4XXX
events have been added in the header file, so use 16-bits for all event
numbers and make them consistent.

No functional change intended.

Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Link: https://lore.kernel.org/r/20220303100710.2238-1-zhangshaokun@hisilicon.comSigned-off-by: Will Deacon <will@kernel.org>