ARM: dts: msm: Disable PIL loading of modem by IPC Router

IPC Router triggers loading the modem by voting to the peripheral
image loader(PIL).

Disable PIL loading of modem by IPC Router to support the Peripheral
Manager which handles loading the modem.

Change-Id: Ib60e51af02c41ed66c64ddd7dfe319f890b406cc
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org>