Don't use "ffs" in an ext2fs sleep message string.

Don't use "ffs" in an ext2fs sleep message string.

Don't forget to clear the inode hash lock before returning from ext2_vget()
after getnewvnode() fails.  Obtained from: rev.1.24 of ffs_vfsops.c (the
original patch for the getnewvnode() race).  Forgotten in: rev.1.4 here.

Removed a duplicate comment.  Duplicated in: rev.1.4 here.

Fixed the MALLOC() vs getnewvnode() race in ext2_vget().  Obtained from:
rev.1.39 of ffs_vfsops.c.