ARM: dts: msm: fix DisplayPort regulator settings on Kona

Fix the regulator min and max voltages and enable load to ensure
that the correct vote is made for the DisplayPort driver.

CRs-Fixed: 2436665
Change-Id: I04a118336bc9c82acbface9af923fc3ced4d2500
Signed-off-by: Tatenda Chipeperekwa <tatendac@codeaurora.org>