ARM: dts: msm: Reduce AQC ring size with PCIe switch on sdxprairie

Reduce AQC ring size for PCIe switch use case in order to conserve
memory for use by other PCIe end-points.

Change-Id: If031877a4b83c9607e417102bddc15e48159de4e
Signed-off-by: Jinesh K. Jayakumar <jineshk@codeaurora.org>