arm64/mm: Drop [PTE|PMD]_TYPE_FAULT

This was added part of the original commit which added MMU definitions.

commit 4f04d8f0 ("arm64: MMU definitions").

These symbols never got used as confirmed from a git log search.

git log -p arch/arm64/ | grep PTE_TYPE_FAULT
git log -p arch/arm64/ | grep PMD_TYPE_FAULT

These probably meant to identify non present entries which can now be
achieved with PMD_SECT_VALID or PTE_VALID bits. Hence just drop these
unused symbols which are not required anymore.

Cc: Will Deacon <will.deacon@arm.com>
Cc: Steve Capper <steve.capper@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>