usb: dwc2: Prevent core suspend when port connection flag is 0

usb: dwc2: Prevent core suspend when port connection flag is 0

In host mode port connection status flag is "0" when loading
the driver. After loading the driver system asserts suspend
which is handled by "_dwc2_hcd_suspend()" function. Before
the system suspend the port connection status is "0". As
result need to check the "port_connect_status" if it is "0",
then skipping entering to suspend.

Cc: <stable@vger.kernel.org> # 5.2
Fixes: 6f6d70597c15 ("usb: dwc2: bus suspend/resume for hosts with DWC2_POWER_DOWN_PARAM_NONE")
Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@synopsys.com>
Link: https://lore.kernel.org/r/20210326102510.BDEDEA005D@mailhost.synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>