audio: The volume is reset after unmuting [1/1]

PD#OTT-64170

Problem:
Unmute without muting, the value is not saved

Solution:
Save the volume when the volume is set

Verify:
zapper

Change-Id: I6d4cc2ce2281da3eb55a60210ec7709989ce055b
Signed-off-by: haiyang.ren <haiyang.ren@amlogic.com>
diff --git a/src/AML_Audio_Setting.cpp b/src/AML_Audio_Setting.cpp
index 6faa36e..8618d41 100644
--- a/src/AML_Audio_Setting.cpp
+++ b/src/AML_Audio_Setting.cpp
@@ -757,6 +757,7 @@
 
     pthread_mutex_lock(&g_volume_lock);
     chip_id = aml_audio_mixer_int(AML_CHIP_ID, 0, false);
+    reserved_volume = value;
     /*s1a use TDM-A as cvbs/hdmi_tx samesource*/
     if (AML_CHIP_ID_S1A == chip_id)
         ret = aml_audio_mixer_int(TDMA_GAIN, value, true);