input: misc: add condition check for ddic reset

LCD can control DDIC reset by itself, so add condition check
and allow not to define DDIC reset pin in device tree.

CRs-Fixed: 1097675
Change-ID: I802bb0ecc86349c7e0380b54811bfae776a41f49
Signed-off-by: Jin Fu <jinf@codeaurora.org>