Add a simplistic memalign() to the runtime_loader heap.

As KMessage now makes use of memalign() the simple heap in the
runtime_loader needs to provide that as well. Fixes build.

src/system/runtime_loader/heap.cpp

@@ -9,6 +9,7 @@
 #include <syscalls.h>
 #include <util/kernel_cpp.h>
 
+#include <malloc.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -318,6 +319,15 @@ restart:
 }
 
 
+void *
+memalign(size_t alignment, size_t size)
+{
+	// pseudo alignment by just upping the size
+	size = (size + alignment - 1) & ~alignment;
+	return malloc(size);
+}
+
+
 void
 free(void *allocated)
 {