update premake5.lua of Lua (#740)

* use compileas

* add cppdialect to dll.lua

* remove src/onelua.c

premake/dll.lua

@@ -68,6 +68,7 @@ include(LUA_DIR)
 project "ocgcore"
 
     kind "SharedLib"
+    cppdialect "C++14"
 
     files { "*.cpp", "*.h" }
     links { "lua" }

premake/lua.lua

 project "lua"
     kind "StaticLib"
-    cppdialect "C++14"
+    compileas "C++"
 
-    files { "src/*.c", "src/*.h", "src/*.hpp" }
-    removefiles { "src/lua.c", "src/luac.c" }
-
-    filter "action:vs*"
-        buildoptions { "/TP" }
-
-    filter "not action:vs*"
-        buildoptions { "-x c++" }
+    files { "src/*.c", "src/*.h" }
+    removefiles { "src/lua.c", "src/luac.c", "src/linit.c", "src/onelua.c" }
 
     filter "configurations:Debug"
         defines { "LUA_USE_APICHECK" }