cr50: util: signer: make signer header definition usable on the target

The signer running on the build host and the loader running on the
target must be in sync as of the structure of the signature header.

To be able to use the same definition in both programs, remove the
system includes from the .h file which needs to be shared. Rearrange
includes in image.cc to follow the coding conventions.

BRANCH=none
BUG=chrome-os-partner:43025
TEST=with the rest of the patches applied the code successfully boots,
     which indicates that the signer is in fact working properly. (See
     the top patch for testing details).

Change-Id: I6bc9c57ebea55ac256fcdac8338c5566f16b6371
Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/311420
Reviewed-by: Nagendra Modadugu <ngm@google.com>

util/signer/common/signed_header.h

@@ -5,10 +5,6 @@
 #ifndef __EC_UTIL_SIGNER_COMMON_SIGNED_HEADER_H
 #define __EC_UTIL_SIGNER_COMMON_SIGNED_HEADER_H
 
-#include <assert.h>
-#include <string.h>
-#include <inttypes.h>
-
 #define FUSE_PADDING 0x55555555  // baked in hw!
 #define FUSE_IGNORE 0xa3badaac   // baked in rom!
 #define FUSE_MAX 128             // baked in rom!

util/signer/image.cc

@@ -2,31 +2,33 @@
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
-#include <common/image.h>
 
-#include <stddef.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <sys/stat.h>
+// global C++ includes
+#include <string>
+
+// global C includes
+#include <assert.h>
 #include <fcntl.h>
-
-#include <libelf.h>
 #include <gelf.h>
-
-#include <common/publickey.h>
-
+#include <libelf.h>
 #include <openssl/bn.h>
 #include <openssl/evp.h>
-#include <openssl/rsa.h>
 #include <openssl/pem.h>
 #include <openssl/rand.h>
+#include <openssl/rsa.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
 
+// local includes
+#include <common/publickey.h>
+#include <common/image.h>
 #include <common/signed_header.h>
 
-#include <string>
 
 using namespace std;