MIPS: tlbex: Better debug output.

Pgtable bits are assigned dynamically depending on processor feature and
statically based on kernel configuration.  To make sense out of the
disassembled TLB exception handlers a list of the actual assignments
used for a particular configuration and hardware setup can be very useful.

Output the actual TLB exception handlers in a format that simplifies their
post processsing from dmesg output.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>