Revert "Flags: add brcm_better_le_scan_params"

This reverts commit 094c1fcf.

This flag will not be used, different approach to this feature bug was
decided.

Test: mma -j68
Bug: 324238597
Bug: 315241296
Change-Id: I7705637f2c35e1e1d031c03505b326ab3ee858ff