ARM: dts: msm: fix order of otg regulator declaration for PMI8950/37

SPMI of_parser stops parsing the SPMI child nodes when it encounters a
non-SPMI child node, thus OTG regulator should be defined at the end of
the charger node after the declaration of all charger peripherals.

Change-Id: Ie2892ab9c8f6ca0d446a9d579cbf94447f812dcb
Signed-off-by: Ashay Jaiswal <ashayj@codeaurora.org>