Early reservation of HID control block

BTA HID host marks the device control block in-use after the connection
is opened. If another connection request is received when a previous
connection is pending, BTA HID host may end up using the same control
block for it.
Device control block should be reserved when
1. Device is added on stack initialization
2. Connection initiated locally
3. Connection initiated by the remote device

Control block finder utilities should be separate from the utility which
finds or allocates the control block.

Test: mmm packages/modules/Bluetooth
Test: Manual | Change preferred HID transport on pairing with earbuds
supporting both DSA 1.0 and DSA 2.0
Flag: EXEMPT bugfix
Bug: 347241319

Change-Id: Id4072f7ba86dd2f26fe22dab0d2080e8a478fea9