Revert "m7-common: show overflow button by default"

This reverts commit e7ec35839ef31d8e8ac60ab48e4583ff8ca158be.

Change-Id: If922c5411777b6aae4faeafc202b14a559c77fc3
m7-common: update hardware keys available

Change-Id: I9b038eaad066b5dba7501ddea62fa15b24e13064