msm: vibrator: Add min/max voltage sysfs entries

Change-Id: Icea99bb76aab73c5ab5bdb0112fbdc081bc62ba6
Signed-off-by: Scott Mertz <smertz@cyngn.com>
Find7: Follow qcom device tree API's about panel's using split

Change-Id: I7690cbcc1ad6139b006b5ae9c939a8c9988e75ee