cifs: map NT_STATUS_ERROR_WRITE_PROTECTED to -EROFS

Seems like a more sensible mapping than -EIO.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/smberr.h b/fs/cifs/smberr.h
index c5084d2..7f16cb8 100644
--- a/fs/cifs/smberr.h
+++ b/fs/cifs/smberr.h
@@ -76,6 +76,7 @@
 #define ERRnofiles		18	/* A File Search command can find no
 					   more files matching the specified
 					   criteria. */
+#define ERRwriteprot		19	/* media is write protected */
 #define ERRgeneral		31
 #define ERRbadshare		32	/* The sharing mode specified for an
 					   Open conflicts with existing FIDs on