add mingw support to msgpack-c (#2166)

packages/m/msgpack-c/xmake.lua

@@ -8,7 +8,7 @@ package("msgpack-c")
     add_versions("4.0.0", "420fe35e7572f2a168d17e660ef981a589c9cbe77faa25eb34a520e1fcc032c8")
 
     add_deps("cmake")
-    on_install("windows", "macosx", "linux", function (package)
+    on_install("windows", "macosx", "linux", "mingw", function (package)
         local configs = {"-DMSGPACK_BUILD_EXAMPLES=OFF", "-DMSGPACK_BUILD_TESTS=OFF", "-DMSGPACK_GEN_COVERAGE=OFF"}
         table.insert(configs, "-DCMAKE_BUILD_TYPE=" .. (package:debug() and "Debug" or "Release"))
         table.insert(configs, "-DBUILD_SHARED_LIBS=" .. (package:config("shared") and "ON" or "OFF"))