staging: r8188eu: summarize tx/rx and scan blinking

Summarize the code for tx/rx blinking and for scan blinking in blink_work.
The only difference is the delay for scheduling the next worker.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Tested-by: Philipp Hortmann <philipp.g.hortmann@gmail.com> # Edimax N150
Link: https://lore.kernel.org/r/20221015151115.232095-11-martin@kaiser.cx


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