ARM: dts: msm: add PCIe endpoint on mdmcalifornium

Add PCIe endpoint node to device tree of mdmcalifornium. PCIe controller
is in endpoint mode and communicates with the PCIe root complex on host
side.

Change-Id: I76df4b4a67beea7d7fba12998ec705e984eef658
Signed-off-by: Yan He <yanhe@codeaurora.org>