ALSA: snd-powermac: enable mic on iMac G4

Allow input from microphone on iMac G4 Flat-panel (Tumbler).
Signed-off-by: Risto Suominen <Risto.Suominen@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/ppc/pmac.c

@@ -1033,7 +1033,7 @@ static int __init snd_pmac_detect(struct snd_pmac *chip)
 	}
 	if (of_device_is_compatible(sound, "tumbler")) {
 		chip->model = PMAC_TUMBLER;
-		chip->can_capture = 0;  /* no capture */
+		chip->can_capture = machine_is_compatible("PowerMac4,2");
 		chip->can_duplex = 0;
 		// chip->can_byte_swap = 0; /* FIXME: check this */
 		chip->num_freqs = ARRAY_SIZE(tumbler_freqs);