When dwc2 core is in partial power down mode
loading driver again causes driver fail. Because in
that mode registers are not accessible.

Added a flow of exiting the partial power down mode
to avoid the driver reload failure.
Acked-by: Minas Harutyunyan <Minas.Harutyunyan@synopsys.com>
Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Link: https://lore.kernel.org/r/20210408094615.8AE35A0094@mailhost.synopsys.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>