support archs with no mlock syscall, only mlock2
diff --git a/src/mman/mlock.c b/src/mman/mlock.c
index e683a44..71af582 100644
--- a/src/mman/mlock.c
+++ b/src/mman/mlock.c
@@ -3,5 +3,9 @@
 
 int mlock(const void *addr, size_t len)
 {
+#ifdef SYS_mlock
 	return syscall(SYS_mlock, addr, len);
+#else
+	return syscall(SYS_mlock2, addr, len, 0);
+#endif
 }