Add minimp3 (#437)

packages/m/minimp3/xmake.lua

@@ -0,0 +1,20 @@
+package("minimp3")
+    set_homepage("https://github.com/lieff/minimp3")
+    set_description("Minimalistic MP3 decoder single header library")
+    set_license("CC0")
+
+    set_urls("https://github.com/lieff/minimp3.git")
+    add_versions("2021.05.29", "b18d274b998cd4406070ddc1f370f53392241af0")
+
+    on_install(function (package)
+        os.cp("*.h", package:installdir("include"))
+    end)
+
+    on_test(function (package)
+        assert(package:check_csnippets({test = [[
+            void test() {
+                mp3dec_t dec;
+                mp3dec_init(&dec);
+            }
+        ]]}, {includes = {"minimp3.h"}}))
+    end)