update mac and linux launch scripts to make mods dir (#3013)

scripts/linux/appimage/soh.sh

@@ -13,6 +13,11 @@ if [ -z ${SHIP_BIN_DIR+x} ]; then
 export SHIP_BIN_DIR="$HERE/usr/bin"
 fi
 
+if [[ ! -e "$SHIP_HOME"/mods ]]; then
+    mkdir -p "$SHIP_HOME"/mods
+    touch "$SHIP_HOME"/mods/custom_otr_files_go_here.txt
+fi
+
 while [[ (! -e "$SHIP_HOME"/oot.otr) || (! -e "$SHIP_HOME"/oot-mq.otr) ]]; do
         for romfile in "$SHIP_HOME"/*.*64
         do