ARM: dts: msm: update panel-maxy for virtual touch key

'panel-maxy' determines the virtual key responsible region.
Current value is too small to touch the virtual key print easily.
So we enlarge it to make it works better.

Change-Id: I7b181bcade9a3eca14cb2876a83de4cad2465ee5
Signed-off-by: Mao Li <maol@codeaurora.org>