[GD-HCI] ACL handle should be AND'ed with 0xFFF instead of 0xEFF

* The spec says that connection handle range is 0x000 to 0xEFF
 * 0xEFF is actually 0b111011111111 (3839)
 * 0x7FF is 0b011111111111 (2047)
* 0x7FF is a valid ACL handle, but if we AND 0x7FF with 0xEFF,
  we get 0b011011111111 which is 0x6FF (1791)

Bug: 203729791
Test: gd/cert/run
Tag: #gd-refactor
Change-Id: I7240f997e502287cd6bbbd6a8b69cef88bd51729