get rid of macOS warning

pxl8.sh

@@ -25,6 +25,7 @@ case "$(uname)" in
         LINKER_FLAGS="$LINKER_FLAGS -rdynamic"
         ;;
     Darwin)
+        export MACOSX_DEPLOYMENT_TARGET="$(sw_vers -productVersion | cut -d '.' -f 1)"
         ;;
     MINGW*|MSYS*|CYGWIN*)
         LINKER_FLAGS="$LINKER_FLAGS -Wl,--export-all-symbols"
@@ -144,10 +145,6 @@ build_luajit() {
         print_info "Building LuaJIT"
         cd lib/luajit
 
-        if [[ "$(uname)" == "Darwin" ]]; then
-            export MACOSX_DEPLOYMENT_TARGET="10.11"
-        fi
-
         make clean >/dev/null 2>&1 || true
         make -j$(nproc 2>/dev/null || echo 4) > /dev/null 2>&1
         cd - > /dev/null