[ALSA] Clean up Makefile

Clean up Makefile using xxx- style instead of
ifeq(CONFIG_XXX,y).

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
diff --git a/sound/core/Makefile b/sound/core/Makefile
index 05f5cdc..3ec303d 100644
--- a/sound/core/Makefile
+++ b/sound/core/Makefile
@@ -3,13 +3,9 @@
 # Copyright (c) 1999,2001 by Jaroslav Kysela <perex@suse.cz>
 #
 
-snd-objs     := sound.o init.o memory.o info.o control.o misc.o device.o
-ifeq ($(CONFIG_ISA_DMA_API),y)
-snd-objs     += isadma.o
-endif
-ifeq ($(CONFIG_SND_OSSEMUL),y)
-snd-objs     += sound_oss.o info_oss.o
-endif
+snd-y     := sound.o init.o memory.o info.o control.o misc.o device.o
+snd-$(CONFIG_ISA_DMA_API) += isadma.o
+snd-$(CONFIG_SND_OSSEMUL) += sound_oss.o info_oss.o
 
 snd-pcm-objs := pcm.o pcm_native.o pcm_lib.o pcm_timer.o pcm_misc.o \
 		pcm_memory.o