media: usbvision: depends on USB

media: usbvision: depends on USB

When built with:
	CONFIG_USB=m
	CONFIG_VIDEO_USBVISION=y

It causes ld errors:

ld: drivers/staging/media/usbvision/usbvision-core.o: in function `usbvision_write_reg_irq':
usbvision-core.c:(.text+0x8a4): undefined reference to `usb_submit_urb'
ld: drivers/staging/media/usbvision/usbvision-core.o: in function `usbvision_isoc_irq':
usbvision-core.c:(.text+0x2ee8): undefined reference to `usb_submit_urb'
ld: drivers/staging/media/usbvision/usbvision-core.o: in function `usbvision_read_reg':
usbvision-core.c:(.text+0x30ad): undefined reference to `usb_control_msg'
ld: drivers/staging/media/usbvision/usbvision-core.o: in function `usbvision_write_reg':
usbvision-core.c:(.text+0x3178): undefined reference to `usb_control_msg'
ld: drivers/staging/media/usbvision/usbvision-core.o: in function `usbvision_set_output':
usbvision-core.c:(.text+0x344e): undefined reference to `usb_control_msg'
ld: drivers/staging/media/usbvision/usbvision-core.o: in function `usbvision_set_input':
usbvision-core.c:(.text+0x3b9b): undefined reference to `usb_control_msg'
ld: drivers/staging/media/usbvision/usbvision-core.o: in function `usbvision_setup':
usbvision-core.c:(.text+0x4009): undefined reference to `usb_control_msg'
ld: drivers/staging/media/usbvision/usbvision-core.o:usbvision-core.c:(.text+0x417f): more undefined references to `usb_control_msg' follow
ld: drivers/staging/media/usbvision/usbvision-core.o: in function `usbvision_set_alternate':
usbvision-core.c:(.text+0x4518): undefined reference to `usb_set_interface'
ld: drivers/staging/media/usbvision/usbvision-core.o: in function `usbvision_init_isoc':
usbvision-core.c:(.text+0x4673): undefined reference to `usb_alloc_urb'
ld: usbvision-core.c:(.text+0x46a5): undefined reference to `usb_alloc_coherent'
ld: usbvision-core.c:(.text+0x4765): undefined reference to `usb_submit_urb'
ld: drivers/staging/media/usbvision/usbvision-core.o: in function `usbvision_stop_isoc':
usbvision-core.c:(.text+0x4837): undefined reference to `usb_kill_urb'
ld: usbvision-core.c:(.text+0x485f): undefined reference to `usb_free_coherent'
ld: usbvision-core.c:(.text+0x4874): undefined reference to `usb_free_urb'
ld: usbvision-core.c:(.text+0x48f1): undefined reference to `usb_set_interface'
ld: drivers/staging/media/usbvision/usbvision-video.o: in function `usbvision_release':
usbvision-video.c:(.text+0x1a8a): undefined reference to `usb_free_urb'
ld: drivers/staging/media/usbvision/usbvision-video.o: in function `usbvision_disconnect':
usbvision-video.c:(.text+0x1b74): undefined reference to `usb_put_dev'
ld: drivers/staging/media/usbvision/usbvision-video.o: in function `usbvision_radio_close':
usbvision-video.c:(.text+0x1c89): undefined reference to `usb_set_interface'
ld: drivers/staging/media/usbvision/usbvision-video.o: in function `usbvision_probe':
usbvision-video.c:(.text+0x1e4b): undefined reference to `usb_get_dev'
ld: usbvision-video.c:(.text+0x20e1): undefined reference to `usb_alloc_urb'
ld: usbvision-video.c:(.text+0x2797): undefined reference to `usb_put_dev'
ld: drivers/staging/media/usbvision/usbvision-video.o: in function `usbvision_exit':
usbvision-video.c:(.exit.text+0x37): undefined reference to `usb_deregister'
ld: drivers/staging/media/usbvision/usbvision-video.o: in function `usbvision_init':
usbvision-video.c:(.init.text+0xf9): undefined reference to `usb_register_driver'
ld: drivers/staging/media/usbvision/usbvision-i2c.o: in function `usbvision_i2c_write':
usbvision-i2c.c:(.text+0x2f4): undefined reference to `usb_control_msg'

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>