powerpc/83xx: Use sizeof correct type when ioremapping

powerpc/83xx: Use sizeof correct type when ioremapping

There is a cut and paste error here so we use sizeof(struct mpc83xx_pmc)
to remap the memory for "clock_regs". That sizeof() is 20 bytes and we
only need to remap 12 bytes. It presumably doesn't affect run time too
much...

I changed them to both use sizeof(*variable_name) because that's the
preferred kernel style these days.

Fixes: e642c9f57caf ("powerpc/mpc83xx: Power Management support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
[mpe: It will map at least one page anyway, but still a good cleanup]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>