arm/dt: 8974: device tree data for virtual keys

Add device tree data for generating virtual keys, and
remove old process of enabling virtual keys which is not
ideal for device tree implementation.  Also enable gen_vkeys
driver so that there is no lapse in virtual key functionality.

CRs-fixed: 430008
Change-Id: Iba362112a8745d344dfddfa7757f2a72fb44e8f4
Signed-off-by: Amy Maloche <amaloche@codeaurora.org>
6 files changed