ARM: dts: msm: fix vdd-mx-supply typo in cpr-regulator node for msm8916

Fix the typo for property vdd-mx-supply which was introduced by commit
b2ddc4c9 ("ARM: dts: msm: add a VDD_APC
cpr-regulator device for msm8916"). Also add qcom,vdd-mx-vmax property
for CPR on msm8916.

Change-Id: Iea02f3eb3e114c679bc931fcb41e636b977bbdf0
Signed-off-by: Fenglin Wu <fenglinw@codeaurora.org>