Separate default role logic and acl paging logic

CTKD doesn't work because both devices think they are peripheral devices. This happens because delayed_role_change_ is "unintendedly" assigned when remote name request is processed (by calling btm_acl_paging). So splitting the default role assign logic and acl paging into 2 functions, and only call the paging logic in remote name request process will solve the problem

Bug:215674668
Test: Manually, follow the reproduction steps in comment#3 b/215674668
and verify the CTKD with "$ adb pull data/misc/bluedroid/bt_config.conf"

Change-Id: I8114059e0b25ff26b4b426148f3d52556cb6f6f4