intel_idle: enable IVB Xeon support

commit 23795e58 upstream.

IVB Xeon currently shares the same parameters IVB client.

For 3.2, add model number to the switch in intel_idle_probe(), as
there is no device ID table.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drivers/idle/intel_idle.c

@@ -419,6 +419,7 @@ static int intel_idle_probe(void)
 		break;
 
 	case 0x3A:	/* IVB */
+	case 0x3E:	/* IVB Xeon */
 		cpuidle_state_table = ivb_cstates;
 		break;