ALSA: powermac - Fix obsoleted machine_is_compatible()

machine_is_compatible() was renamed to of_machine_is_compatible().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/ppc/tumbler.c b/sound/ppc/tumbler.c
index 0b69e96..20afdf9 100644
--- a/sound/ppc/tumbler.c
+++ b/sound/ppc/tumbler.c
@@ -47,7 +47,7 @@
 #define DBG(fmt...)
 #endif
 
-#define IS_G4DA (machine_is_compatible("PowerMac3,4"))
+#define IS_G4DA (of_machine_is_compatible("PowerMac3,4"))
 
 /* i2c address for tumbler */
 #define TAS_I2C_ADDR	0x34