arm/dt: 8974: disable charging for Fluid and MTP

Having charging enabled on Fluid and MTP devices
causes resets caused by DC supplies emulating
VBAT on provided large debug boards for the platform.

While battery presence continues to be emulated on
these boards disable charging by default to avoid
above mentioned resets.

Change-Id: Ieb5238d80866f1cd9e36281ce2c6fa766603a1b3
Signed-off-by: David Keitel <dkeitel@codeaurora.org>