Prevent CL_RunCinematic from reading cinTable[-1]

At the end of CL_RunCinematic, RoQShutdown sets currentHandle to -1.
This causes the return at the end to be return cinTable[-1].status.
Use return FMV_EOF when RoQShutdown is called.

I think FMV_EOF should be returned instead of FMV_IDLE which is set in
RoQShutdown because RoQShutdown is clearing out state so it can be reused
for a new cinematic.

The return value isn't actually read by the ioq3 client, renderers,
cgame, or ui.

code/client/cl_cin.c

@@ -1384,6 +1384,7 @@ e_status CIN_RunCinematic (int handle)
 		RoQReset();
 	  } else {
 		RoQShutdown();
+		return FMV_EOF;
 	  }
 	}