input: touchscreen: Add virtual key support from dtsi

Add virtual key support from device tree node and
corrected the sequence of virtual keys defined in
dtsi for Goodix driver.

CRs-fixed: 567499
Change-Id: Iee1db2eb07c00fd4338255b9648fac5e05aa9c6d
Signed-off-by: Shantanu Jain <shjain@codeaurora.org>