staging: r8188eu: remove unused dm_priv components

Remove unused components from struct dm_priv.

DMFlag is only written to, but never read.
InitDMFlag is assigned to DMFlag and not used elsewhere.
DM_Type is also write-only.
UndecoratedSmoothedPWDB and UndecoratedSmoothedCCK are not used at all.

Acked-by: Phillip Potter <phil@philpotter.co.uk>
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20211020195401.12931-1-martin@kaiser.cx


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