platform: correct EOT_PACKET_CTRL register offset on 8x10

This fixes the wrong offset introduced in the commit:
If1157f69300735511ff1011e65f459370f92bdea. On 8x10, it
is using DSI-v2 controller. The register offset is different
from the other B-family targets.

Change-Id: I1999e3c376c5d05b603bb76aed2c6a1d17901b5c
1 file changed