ANDROID: Add usb dwc3 & gadget headers to unsafe header

	The mainline header files are necessary to support dwc3 & gadget functions
	when applying DDK to exynos USB driver. So, added some header files under drivers/usb/
	in unsafe header group for using them.

	- The headers in 'drivers/usb/dwc3 & host/' are used for dwc3-eyxnos-usb.ko DDK module
	- The headers in 'drivers/usb/gadget/' are used for usb_f_dm.ko & usb_f_rndis_mp.ko DDK
	  modules

Bug: 380797910
Change-Id: I9f84dc45219f88d8dac258aa0ac4f323fdf1c76a
Signed-off-by: Eomji Oh <eomji.oh@samsung.com>
Signed-off-by: Hongseock Kim <hongpooh.kim@samsung.com>