powerpc/xmon: Don't print hashed pointers in paca dump

Remember when the biggest problem we had to worry about was hashed
pointers, those were the days.

These were missed in my earlier patch because they don't match "%p",
but the macro is hiding a "%p", so these all end up being hashed,
which is not what we want in xmon. Convert them to "%px".

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>