Add NSFW/SFW board filter to /all/ board page on mobile (#1071)

* feat(board-buttons): add NSFW/SFW filter to /all/ board page on mobile

* refactor(board-buttons): extract MobileAllFeedFilter padding to CSS class

src/components/board-buttons/board-buttons.tsx

@@ -364,6 +364,15 @@ const AllFeedFilter = () => {
   );
 };
 
+export const MobileAllFeedFilter = () => (
+  <div className={styles.mobileBoardButtons}>
+    <hr />
+    <div className={`${styles.options} ${styles.mobileAllFeedFilterPadding}`}>
+      <AllFeedFilter />
+    </div>
+  </div>
+);
+
 export const MobileBoardButtons = () => {
   const { t } = useTranslation();
   const params = useParams();