pinctrl: msm: Add input enable support to tlmm

Add input enable support to tlmm. This support
is needed to achieve higher power savings by
configuring any unused pin as input and bias-pull-down.

CRs-Fixed: 668615
Change-Id: I1a3042c2b6a0d01c8014b75852c544227b00cbaa
Signed-off-by: Kaushal Kumar <kaushalk@codeaurora.org>