ARM: dts: msm: Increase MHI timeout for WLAN on SM8150

Currently WLAN QCA6390 device RAM dump collection will take about
8 seconds. Increase MHI timeout to 10 seocnds to avoid timeout.

Change-Id: Ib3ba97594ed9b2f4f60316e0a5be179ba3603a48
Signed-off-by: Yue Ma <yuem@codeaurora.org>