arm64: mm: Add pgprot_pbha() to allow drivers to request PBHA values

maillist inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I7ZC0H

Reference: https://lore.kernel.org/all/20211015161416.2196-1-james.morse@arm.com/t/#u



--------------------------------

Add a pgprot_pbha() helper that modifies a pgprot_t to include a pbha
value. The value is checked against those that were listed as only
affecting performance.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Ma Wupeng <mawupeng1@huawei.com>