input: sensor: msm8610: Fix accelerometer working on wrong mode issue

Accelerometer Kionix kxtj9 always outputs 8-bit data because assign
a boolean value to bit mask variable. This patch will fix this and
also change the resolution control variable name from "res_12bit"
to "res_ctl" to avoid misleading.

Change-Id: I4784bfb18679a1a64941eafc80762241cdd825fe
Signed-off-by: Figo Wang <figow@codeaurora.org>