A bunch of minor cleanups when using sizeof(). This even appears to have

A bunch of minor cleanups when using sizeof().  This even appears to have
caught 3 minor bugs in the code.  Prompted by a couple of similar bugs that
were just found in the kernel.

Basically, with a variable like "struct foo *bar" it is preferrable to
use "sizeof(*bar)" everywhere instead of "sizeof(struct foo)".  The
former isolates us from errors in case the type of "bad" ever changes.

Apparent bugs were in filter/filter_obd.c and ldlm/ldlm_resource.c (we
were using __u32 when the variable was declared as __u64).  There also
appears to be a memory leak in ldlm_resource.c.