Declare C malloc/free in stdlib.d

Author: deadalnix

sdlib/core/stdc/stdlib.d

@@ -1,8 +1,14 @@
 module core.stdc.stdlib;
 
-extern (C):
+extern(C):
+
 // @trusted: // Types only.
 // nothrow:
 // @nogc:
 
+void* malloc(size_t size);
+void free(void* ptr);
+void* calloc(size_t nmemb, size_t size);
+void* realloc(void* ptr, size_t size);
+
 void exit(int code);