MFC r270507:
MFC r270507:

Fix bug that, assuming a/ is a root of NFS filesystem mounted on autofs,
prevented "mv a/from a/to" from working, while "cd a && mv from to" was ok.

PR:		192948
Sponsored by:	The FreeBSD Foundation

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase