input: touchscreen: st: update firmware without userhelper

When CONFIG_FW_LOADER_USER_HELPER is set, request_firmware()
falls back to the usermode helper for loading via udev which
cause too long timeout (60 seconds) when the direct loading
fails. By this patch, the fts firmware is updated via the
request_firmware_direct but not request_firmware, which can
save that uncessage timeout during every bootup. That is
critical during off-mode charging.

CRs-Fixed: 2236297
Change-Id: Icbebd1a5a3bbe8dc4a90aab467b4d6c614cb9edf
Signed-off-by: John Zhao <yuankuiz@codeaurora.org>