Fix a memory leak in __getcwd() that can occur after a filesystem has been forcibly unmounted. If the filesystem root vnode is reached and it has no associated mountpoint (vp->v_mount == NULL), __getcwd would return without freeing 'buf'. Add the missing free() call.
Fix a memory leak in __getcwd() that can occur after a filesystem
has been forcibly unmounted. If the filesystem root vnode is reached
and it has no associated mountpoint (vp->v_mount == NULL), __getcwd
would return without freeing 'buf'. Add the missing free() call.

PR:		kern/30306
Submitted by:	Mike Potanin <potanin@mccme.ru>
MFC after:	1 week

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