arm64: mm: move pte_* macros

For pmd, pud, and pgd levels of table, functions including p?d_index and
p?d_offset are defined after the p?d_page_vaddr function for the
immediately higher level of table.

The pte functions however are defined much earlier, even though several
rely on the later definition of pmd_page_vaddr. While this isn't
currently a problem as these are macros, it prevents the logical
grouping of later C functions (which cannot rely on prototypes for
functions not yet defined).

Move these definitions after pmd_page_vaddr, for consistency with the
placement of these functions for other levels of table.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Cc: Laura Abbott <labbott@fedoraproject.org>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>