staging: r8188eu: make odm_DIG() static

Function odm_DIG() is used only in odm.c. Make it static.

Signed-off-by: Michael Straube <straube.linux@gmail.com>
Link: https://lore.kernel.org/r/20211229205108.26373-17-straube.linux@gmail.com


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