Disabling all EP's allow to reset EP's to initial state.
On disconnect disable all EP's instead of just killing
all requests. Because of some platform didn't catch
disconnect event, same stuff added to
dwc2_hsotg_core_init_disconnected() function when USB
reset detected on the bus.

Changed from version 1:
Changed lock acquire flow in dwc2_hsotg_ep_disable()
function.
Signed-off-by: Minas Harutyunyan <hminas@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>