Refer newfs and growfs users to fsck_ffs instead of
fsck, the latter does not accept the referred to "-b" flag.

This change was accidently committed directly to 9-STABLE in
r237505.

PR:		82720
Submitted by:	David D.W. Downey
MFC after:	1 week
Use vm_paddr_t, not vm_offset_t, when dealing with physical addresses.

Pointed out by:	alc