Support BTN_TOOL_*TAP as synonyms for BTN_TOOL_FINGER.

Bug: 5205301

Some drivers report one finger as BTN_TOOL_FINGER, two as
BTN_TOOL_DOUBLETAP, three as BTN_TOOL_TRIPLETAP and four
as BTN_TOOL_QUADTAP.  Since we care about the tool type,
we need to handle _DOUBLE/_TRIPLE/_QUAD tap in the same way
we handle _FINGER.

Change-Id: I8eb83d2a2bada9ac32d07619c7eea84e924316b8