Store volume only when Hearing Aid devices are not active

To avoid store wrong steam volume for A2DP device when switch active
devices from A2DP to Hearing Aid. Only store volume for A2DP device
when Hearing Aid device are not active.

Bug: 132747109
Test: Manually switch active device from A2DP to Hearing Aid
Merged-In: I8edc03b5f139f87d455ea2fde60ce8d84f2484b9
Change-Id: I8edc03b5f139f87d455ea2fde60ce8d84f2484b9