Remove useless line

auth_req is either BTM_AUTH_AP_NO (2) or BTM_AUTH_AP_YES (3).
BTM_AUTH_DD_BOND is 2.  Useless or.

Bug: 163134718
Tag: #refactor
Test: compile & verify basic functions working
Change-Id: If34b501892d3bb2b4186710c5a64f4193cb939c8