Add dlltool toolset for mingw

Author: star-hengxing

xmake/modules/package/tools/meson.lua

@@ -261,6 +261,10 @@ function _get_configs_file(package, opt)
             if mrc then
                 file:print("windres=['%s']", executable_path(mrc))
             end
+            local dlltool = package:build_getenv("dlltool")
+            if dlltool then
+                file:print("dlltool=['%s']", executable_path(dlltool))
+            end
         end
         local cmake = find_tool("cmake")
         if cmake then

xmake/toolchains/mingw/xmake.lua

@@ -67,6 +67,7 @@ toolchain("mingw")
         toolchain:add("toolset", "ranlib", cross .. "ranlib")
         toolchain:add("toolset", "objcopy", cross .. "objcopy")
         toolchain:add("toolset", "mrc", cross .. "windres")
+        toolchain:add("toolset", "dlltool", cross .. "dlltool")
         if is_host("windows") and bindir then
             -- we use bin/gcc.exe if cross not found
             -- @see https://github.com/xmake-io/xmake/issues/977#issuecomment-704863677
@@ -77,6 +78,7 @@ toolchain("mingw")
             toolchain:add("toolset", "ld", path.join(bindir, "g++"), path.join(bindir, "gcc"))
             toolchain:add("toolset", "sh", path.join(bindir, "g++"), path.join(bindir, "gcc"))
             toolchain:add("toolset", "mrc", path.join(bindir, "windres"))
+            toolchain:add("toolset", "dlltool", path.join(bindir, "dlltool"))
         end
 
         -- init flags for architecture