Remove unncessary HID host control block states

HID host states BTIF_HH_DEV_UNKNOWN, BTIF_HH_DEV_CONNECTING and
BTIF_HH_DEV_CONNECTED are irrelevant. Of these only
BTIF_HH_DEV_CONNECTING is used for tracking outgoing connection attempt
which can be found by pending connection address as well.
There may be multiple outgoing connection pending, so pending_link_spec
is converted to a list.

Test: mmm packages/modules/Bluetooth
Flag: EXEMPT mechanical refactor
Bug: 347241319
Change-Id: Ic57c8d7665ddf6b1c18eea28e2e60a59a81c0338