input: touchscreen: Add firmware upgrade via sysfs entry

Add sysfs entry for firmware upgrade support in Goodix
driver.

This patch is propagated from msm-3.10 kernel.
(commit: a8f22042f8816658cb8247c931c1725886350a8b
input: touchscreen: Add firmware upgrade via sysfs entry)

CRs-fixed: 575618
Change-Id: If71d4020223547e0db425c9fd37819c6166efcab
Signed-off-by: Shantanu Jain <shjain@codeaurora.org>