This fixes a large batch of warnings that popped up with the new stricter
bitops.h that recently was introduced.  We actually didn't have 64-bit
bug, but we had built our own *_flags_t typedef's that were just struct
wrappers around an unsigned long.  We used to pass their addresses directly
to set_bit() and friends but now that causes an error.  The typedef's really
didn't serve much purpose so the cleanest fix is to just eliminate them and
use "unsigned long" directly.