arm64: add sentinel to kpti_safe_list

arm64: add sentinel to kpti_safe_list

We're missing a sentinel entry in kpti_safe_list. Thus is_midr_in_range_list()
can walk past the end of kpti_safe_list. Depending on the contents of memory,
this could erroneously match a CPU's MIDR, cause a data abort, or other bad
outcomes.

Add the sentinel entry to avoid this.

Fixes: be5b299830c63ed7 ("arm64: capabilities: Add support for checks based on a list of MIDRs")
Signed-off-by: Mark Rutland <[email protected]>
Reported-by: Jan Kiszka <[email protected]>
Tested-by: Jan Kiszka <[email protected]>
Reviewed-by: Suzuki K Poulose <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Suzuki K Poulose <[email protected]>
Cc: Will Deacon <[email protected]>
Signed-off-by: Will Deacon <[email protected]>