ARM: dts: msm: Update GPU chipid for SDM429

The SDM429 GPU is similar to SDM439 but has
different clock plan. Update SDM429 GPU ID to
A504 so that we can handle it.

Change-Id: I6bf6c7f020272eadb378df3c00af867f053d13b2
Signed-off-by: Hareesh Gundu <hareeshg@codeaurora.org>