vold: remove unnecessary dependency on libbatteryservice.

Battery check could be replaced by hwbinder calls into
android.hardware.health@2.0 instead, but because
of b/16868177, this is actually not needed.

Bug: 62229583
Test: pass
Change-Id: Ieb03e6ee2f648d9c1d85dbbdc10626726f5fe39b
2 files changed