sysinstall fails on 3/31 -current iso

[Nate Lawson]

I was installing from a snapshot generated by snapshots.jp.freebsd.org and
got a panic when entering the fdisk screen.  I can try for a backtrace
later but it was in a call to ufs_mkdir which called a softdep function.
Anyone else seen this?  It may be a result of DEBUG_VFS_LOCKS or some
other debugging feature on in -current but not releases.  5.1 and 5.2
install on the same box ok.

-Nate