DO NOT MERGE HFP: Check AT command buffer boundary during parsing

* add p_end parameter to tBTA_AG_AT_CMD_CBACK, bta_ag_at_hsp_cback
  and bta_ag_at_hfp_cback to indicate effective data range of p_arg
* add checks for buffer copy overflow in bta_ag_at_hsp_cback and
  bta_ag_at_hfp_cback
* add packet legnth checks with p_end in bta_ag_parse_cmer
* add packet length checks with p_end in bta_ag_parse_bac

Bug: 112860487
Test: manual
Change-Id: Idbfa2b8bd4c1a0aeeacfe34349851b3bc8de7c69
Merged-In: Idbfa2b8bd4c1a0aeeacfe34349851b3bc8de7c69
(cherry picked from commit 5b1ef1038e3f4e4371c3d6718bf0f684be65eb2b)