staging: r8188eu: remove LastMinUndecoratedPWDBForDM

LastMinUndecoratedPWDBForDM in struct dm_priv is not used. Remove it.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20211011201159.10252-5-martin@kaiser.cx


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