Relax encryption supported requirements

The output of vdc cryptfs enablecrypto recently changed from
"500 Usage: cryptfs enablecrypto <wipe|inplace> <passwd>" to
"500 0 Usage: cryptfs enablecrypto <wipe|inplace> <passwd>". Relax
requirements to start with 500 and contain "Usage: "

Change-Id: Ia3455907e980aeb7f39228fe08f7eccd7fade8ea
1 file changed