staging: gpib: Update messaging and usb_device refs in agilent_usb

Replace GPIB_DPRINTK with dev_dbg
Replace pr_xxx with dev_xxx wherever possible
Use previously initialized usb_device pointer for usb_put_dev()
Remove commented out console message code.

Signed-off-by: Dave Penkler <dpenkler@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/20241104175014.12317-5-dpenkler@gmail.com


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