powerpc/fsl-booke: Fix mapping functions to use phys_addr_t

Fixed v_mapped_by_tlbcam() and p_mapped_by_tlbcam() to use phys_addr_t
instead of unsigned long.  In 36-bit physical mode we really need these
functions to deal with phys_addr_t when trying to match a physical
address or when returning one.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>