arm64: extable: make uaaccess helper use extable type EX_TYPE_UACCESS_ERR_ZERO

Currnetly, the extable type used by __arch_copy_from/to_user() is
EX_TYPE_FIXUP. In fact, It is more clearly to use meaningful
EX_TYPE_UACCESS_*.

Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Tong Tiangen <tongtiangen@huawei.com>
Link: https://lore.kernel.org/r/20220621072638.1273594-5-tongtiangen@huawei.com


Signed-off-by: Will Deacon <will@kernel.org>