staging: r8188eu: remove unused struct hostapd_priv

struct hostapd_priv contains only a pointer to struct adapter.

Remove this struct and the unused phostapdpriv pointer in struct adapter.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20220206161809.423031-15-martin@kaiser.cx


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