staging: r8188eu: remove unnecessary category check

Remove the unnecessary category check in issue_action_BA. category is
initialised to 3 (WLAN_CATEGORY_BACK) and never updated.

The rtw_set_fixed_ie call gets a pointer to category but it doesn't update
the value.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20220524090029.242584-2-martin@kaiser.cx


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