configure: formatting cosmetics

configure

@@ -1967,13 +1967,17 @@ do_random(){
 for opt do
     optval="${opt#*=}"
     case "$opt" in
-        --extra-ldflags=*) add_ldflags $optval
+        --extra-ldflags=*)
+            add_ldflags $optval
         ;;
-        --extra-libs=*) add_extralibs $optval
+        --extra-libs=*)
+            add_extralibs $optval
         ;;
-        --disable-devices) disable $INDEV_LIST $OUTDEV_LIST
+        --disable-devices)
+            disable $INDEV_LIST $OUTDEV_LIST
         ;;
-        --enable-debug=*) debuglevel="$optval"
+        --enable-debug=*)
+            debuglevel="$optval"
         ;;
         --disable-programs)
             disable $PROGRAM_LIST