x86/pkeys: Clarify PKRU_AD_KEY macro
When changing the PKRU_AD_KEY macro to be used for PKS the name came
into question.[1]
The intent of PKRU_AD_KEY is to set an initial value for the PKRU
register but that is just a mask value.
Clarify this by changing the name to PKRU_AD_MASK().
NOTE the checkpatch errors are ignored for the init_pkru_value to align
the values in the code.
[1] https://lore.kernel.org/lkml/
eff862e2-bfaa-9e12-42b5-
a12467d72a22@intel.com/
Suggested-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20220419170649.1022246-3-ira.weiny@intel.com