headers: Move err.h to common

travis-ci: success for headers: Finalize include/common/
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

criu/include/bfd.h

 #ifndef __CR_BFD_H__
 #define __CR_BFD_H__
 
-#include "err.h"
+#include "common/err.h"
 
 struct bfd_buf;
 struct xbuf {

criu/include/util.h

@@ -17,7 +17,7 @@
 #include "xmalloc.h"
 #include "common/bug.h"
 #include "log.h"
-#include "err.h"
+#include "common/err.h"
 
 #define PREF_SHIFT_OP(pref, op, size)	((size) op (pref ##BYTES_SHIFT))
 #define KBYTES_SHIFT	10

criu/include/err.h → include/common/err.h

 /*
  * Adopted from linux kernel
  */
-#ifndef __CR_ERR_H__
-#define __CR_ERR_H__
+#ifndef __CR_COMMON_ERR_H__
+#define __CR_COMMON_ERR_H__
 
 #include "common/compiler.h"