powerpc/eeh_cache: Add pr_debug() prints for insert/remove

The EEH address cache is used to map a physical MMIO address back to a PCI
device. It's useful to know when it's being manipulated, but currently this
requires recompiling with #define DEBUG set. This is pointless since we
have dynamic_debug nowdays, so remove the #ifdef guard and add a pr_debug()
for the remove case too.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>