arm64/pi: Tweak map_range() to allow block mappings to be avoided

Interpret the PTE_TABLE_BIT in the pgprot argument to map_range() as an
indication that only table and page mappings should be created, and
block mappings should be avoided even if the alignment and size of the
region would permit using those.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>