input: synaptics_dsx_2.6: Add support for clocks for secure touch

Because of a change in the underlying bus driver, the secure touch
layer in the input drivers is now required to control directly the
clocks which are needed during the touch sessions. The clocks which
are associated with the underlying I2C bus are clk_gcc_blsp1_ahb_clk
and clk_gcc_blsp1_qup3_i2c_apps_clk. These clocks are turned on/off
when the secure touch session is started/ended.

CRs-Fixed: 990820
Change-Id: Ie2f6f5b736b27792e6e4dc2c39064e0ebdc03d7b
Signed-off-by: Shantanu Jain <shjain@codeaurora.org>
Signed-off-by: Abinaya P <abinayap@codeaurora.org>