GD Security: InternalEnforceSecurityPolicy

Currently, the logic is a little confusing, this CL should simplify it.

Bug: 162984360
Tag: #gd-refactor
Test: cert/run --host SecurityTest:test_dut_initiated_no_input_no_output_no_input_no_output_twice_bond_and_enforce
Test: atest --host bluetooth_test_gd
Change-Id: I19753a29487c4bf2c3b40189c0576526d39657c8