HCI: Add SetEventMaskPage2 Opcode

SetEventMaskPage2 is used for enabling/disabling
events for AMP.  Although we don't support these,
we can support (ignore) the command to disable them.

Bug: 186458975
Test: cert/run
Tag: #gd-refactor
Change-Id: Ibe957895fb830baf93b796a6b375928884912e18