pcl: include headers for getpid and memcpy

src/pcl/pcl.c

@@ -22,6 +22,8 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
 #include "pcl_config.h"
 #include "pcl.h"
 #include "pcl_private.h"