Replace BTM_BLI_PAGE_EVT & BTM_BLI_PAGE_DONE_EVT with btm_acl_set_paging

It was only used to set a btm_cb.is_paging, and never reported

Bug: 159815595
Tag: #refactor
Test: compile & verify basic functions working
Change-Id: Ia15f255a1abb53a4a8099aa635123a042912040d