input: touchpanel: fix security issues in GT915 driver

There are multiple buffer overflow and input validation issues
in Goodix gt915 driver, fix these issues by adding data length
check and change file system node mode.

CRs-Fixed: 526101
Change-Id: I5173fc1ca021fd45c939c7c8a4f460651330de5b
Signed-off-by: Bingzhe Cai <bingzhec@codeaurora.org>