usb: dwc3: core: Fix unused variable warning in core driver

While fixing a merge conflict in linux-next, hw_mode variable
was left unused. Remove the unused variable in hs_phy_setup call.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/all/202405030439.AH8NR0Mg-lkp@intel.com/


Signed-off-by: Krishna Kurapati <quic_kriskura@quicinc.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/20240506074939.1833835-1-quic_kriskura@quicinc.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>