the code auto-generated for *.m - kobj_lookup_method(9) is useful;
for example in back-ends or base class device drivers in order to
determine whether a default method has been overridden. Thus, allow
for the kobj_method_t pointer argument - used by KOBJOPLOOKUP in
order to update the cache entry - of kobj_lookup_method(9), to be
NULL. Actually, that pointer is redundant as it's just set to the
same kobj_method_t that the kobj_lookup_method(9) function returns
in the first place, but probably it serves to reduce the number of
instructions generated for KOBJOPLOOKUP.
- For the same reason, move updating kobj_lookup_{hits,misses} (if
KOBJ_STATS is defined) from kobj_lookup_method(9) to KOBJOPLOOKUP.
As a side-effect, this gets rid of the convoluted approach of always
incrementing kobj_lookup_hits in KOBJOPLOOKUP and then in case of
a cache miss, decrementing it in kobj_lookup_method(9) again.
