flock: use nfs4 fallback on EBADF too

The kernel regression (probably v3.4, commit 55725513) introduces a
new errno for O_RDONLY on NFS. Now it returns EBADF rather than EIO.

Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=1078618
Signed-off-by: Karel Zak <kzak@redhat.com>

sys-utils/flock.c

@@ -250,6 +250,7 @@ int main(int argc, char *argv[])
 			/* otherwise try again */
 			continue;
 		case EIO:
+		case EBADF:		/* since Linux 3.4 (commit 55725513) */
 			/* Probably NFSv4 where flock() is emulated by fcntl().
 			 * Let's try to reopen in read-write mode.
 			 */