drivers: synaptics_3k: wrap i2c operations with mutex

This seems to help with dead touchscreen issue on ace. Idea came
from jianC.
Merge branch 'cm-11.0-wip' into cm-11.0
Revert "drivers: synaptics_3k: wrap i2c operations with mutex"

This reverts commit f941a0781c5e606843badd5bf5572a0093166a19.
Merge branch 'cm-11.0-wip' into cm-11.0
Merge branch 'cm-11.0' of https://github.com/AceEnablementProject/android_kernel_htc_msm7x30 into kk_mkt