[ALSA] Move vmaster code to sound core

Move the codes for virtual master controls to sound core part so that
not only hda-intel drivers can use it.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/core/Makefile b/sound/core/Makefile
index 267039a9..da8e685 100644
--- a/sound/core/Makefile
+++ b/sound/core/Makefile
@@ -6,6 +6,7 @@
 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-$(CONFIG_SND_VMASTER) += vmaster.o
 
 snd-pcm-objs := pcm.o pcm_native.o pcm_lib.o pcm_timer.o pcm_misc.o \
 		pcm_memory.o