usb: dwc3: document gfladj_refclk_lpm_sel field

Avoid a kernel-doc warning by documenting it:
	drivers/usb/dwc3/core.h:1343: warning:
	  Function parameter or member 'gfladj_refclk_lpm_sel'
          not described in 'dwc3'

Fixes: a6fc2f1b ("usb: dwc3: core: add gfladj_refclk_lpm_sel quirk")
Signed-off-by: Swarup Laxman Kotiaklapudi <swarupkotikalapudi@gmail.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/20231002210137.209382-1-swarupkotikalapudi@gmail.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/dwc3/core.h

@@ -1115,6 +1115,8 @@ struct dwc3_scratchpad_array {
  *			instances in park mode.
  * @parkmode_disable_hs_quirk: set if we need to disable all HishSpeed
  *			instances in park mode.
+ * @gfladj_refclk_lpm_sel: set if we need to enable SOF/ITP counter
+ *                          running based on ref_clk
  * @tx_de_emphasis_quirk: set if we enable Tx de-emphasis quirk
  * @tx_de_emphasis: Tx de-emphasis value
  *	0	- -6dB de-emphasis