[EN]
1. Improve AGC algorithm
2. Improve I/Q balance algoritm
3. Added CI-V command to switch between built-in/external speakers:
   1D 02 01 [XX]
   XX=0: Built-in speaker
   XX!=0: External speaker(MIC handle speaker)

[CH]
1. 改进AGC算法
2. 改进I/Q平衡算法
3. 新增切换内置/外部扬声器的CI-V指令:
   1D 02 01 [XX]
   XX=0:内置扬声器
   XX!=0:外部扬声器(手咪扬声器)
