Increase BTA_JV_PM_MAX_NUM to 12 to consider multi connections.

In AOSP code, the number of PM_TIMER (BTA_JV_PM_MAX_NUM) is restricted to just only 5, it's not enough considering multi connections. So a service session after 6th can't be allocated PM_TIMER, then it can't manage to sniff/unsniff for the link (eg, changing to sniff state even while data transferring). So it need to increase the BTA_JV_PM_MAX_NUM value enoughly.

Bug: 238988758
Bug: 245580288
Flag: EXEMPT Just a config change and should ideally be no-op/
Test: m -j $(nproc)
Change-Id: Ie386196331809059579420935b7560725d8718f8