HBS1098 Paring failure after connection with Car-Audio

Use Case: HBS1100 Paring failure after connection with Car-Audio

Steps:
1. Establish connection with Volkswagen CK, and then playback music
2. Try to pair with HBS-1100

Failure: DUT going for temporary pairing with HBS1100 when request received
while remote name is not present

Root Cause: As auth_req is not handled properly in bta_dm_pinname_cback during
RNR, auth_req variable got reset and DUT is going for temporary pairing.

Fix: local and remote auth_req and local and remote IO capabilities stored and
retained in call backs properly.

Test: Manually tested

Fixes: 35735338

Change-Id: I83382aac9fc1197d7fb31feedbd0fe3b35de87e8