ARM: dts: msm: Update the link information for sm8150+sdx50

Update the PCIe link information for the sm8150+sdx50 platform
with the correct value.

Change-Id: I6a81f80b59e19216cde099a6e1174ebcb9d567d9
Signed-off-by: Raghavendra Rao Ananta <rananta@codeaurora.org>