InputMapper refactor: TouchpadInputMapper

Add a factory method for TouchpadInputMapper to be configured on
initilisation

Test: m checkinput && atest libinput_tests inputflinger_tests
Bug: 256009910
Change-Id: I1189eede635330b24f3f1175d2aa4b46775362b7
(cherry picked from commit 04e643ceacce438363afb521b7a1ff429562aab7)
2 files changed