vrecycle() is typically called from a VFS's inactive function, which
in turn is called when the sysref reference count transitions from
1->0xc0000000. Fix a test that was causing the vnode to not be immediately
recycled.
msdosfs depended on the recyclement behavior due to rename-over issues -
msdosfs is not allowed to reuse an 'inode' (which is basically the position
of a directory entry in a directory) until the underlying file is entirely
reclaimed.
This also effected ufs somewhat by preventing inodes from being reused as
quickly as they could be, but ufs allocates inodes dynamically and masked
the problem.
Reported-by: walt <wa1ter@myrealbox.com>