usb: dwc2: disable Link Power Management on STM32MP15 HS OTG

Link Power Management (LPM) on STM32MP15 OTG HS encounters instabilities
with some Host controllers. OTG core fails to exit L1 state in 200us:
"dwc2 49000000.usb-otg: Failed to exit L1 sleep state in 200us."
Then the device is still not enumerated.

To avoid this issue, disable Link Power Management on STM32MP15 HS OTG.

Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Amelie Delaunay <amelie.delaunay@foss.st.com>
Link: https://lore.kernel.org/r/20210105094855.30763-4-amelie.delaunay@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>