git-p4: fix problem when p4 login is not necessary

In a perforce setup where login is not required, communication fails
because p4_check_access does not understand the response from the p4
client. Fixed by detecting and ignoring the "info" response.

Signed-off-by: Peter Osterlund <peterosterlund2@gmail.com>
Acked-by: Luke Diamand <luke@diamand.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-p4.py

@@ -332,6 +332,8 @@ def p4_check_access(min_expiration=1):
             die_bad_access("p4 error: {0}".format(data))
         else:
             die_bad_access("unknown error")
+    elif code == "info":
+        return
     else:
         die_bad_access("unknown error code {0}".format(code))