Audio : add snd-aloop and snd-dummy modules.

Change-Id: I41c1471005ae8c869f67c0845a91df23fe996507

Author: yupei_lin

arch/arm/configs/rockchip_linux_defconfig

@@ -607,6 +607,8 @@ CONFIG_SND_SOC_RT5616=y
 CONFIG_SND_SOC_RT5640=y
 CONFIG_SND_SOC_SPDIF=y
 CONFIG_SND_SIMPLE_CARD=y
+CONFIG_SND_ALOOP=m
+CONFIG_SND_DUMMY=m
 CONFIG_SOUND_PRIME=y
 CONFIG_HID_BATTERY_STRENGTH=y
 CONFIG_HIDRAW=y