staging: r8188eu: merge on_action_public_default into its only caller

Merge on_action_public_default into on_action_public, which is the only
caller. Yet again, this makes the code a tiny bit smaller.

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/20221230175326.90617-3-martin@kaiser.cx


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