ARM: dts: stm32: osd32: move usb phy power to common

According to the OSD32MP1 Power System overview[1] usb phy power is
hard-wired internally in the SIP module to ldo4.

[1]:
https://octavosystems.com/app_notes/osd32mp1-power-system-overview/#connections



Signed-off-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Alexandre Torgue <alexandre.torgue@foss.st.com>