Make kernel signature a part of the kernel preamble.

With this change, the kernel signature is a part of the preamble block (and therefore, used during preamble signature verification).

BUG=670
TEST=image verification tests still pass. corrected splicing test expectations (and it passes).

Review URL: http://codereview.chromium.org/2292001
diff --git a/tests/test_common.h b/tests/test_common.h
index d73dc0e..c840415 100644
--- a/tests/test_common.h
+++ b/tests/test_common.h
@@ -13,9 +13,13 @@
 #include "kernel_image.h"
 
 extern int gTestSuccess;
+
 /* Return 1 if result is equal to expected_result, else return 0.
  * Also update the global gTestSuccess flag if test fails. */
 int TEST_EQ(int result, int expected_result, char* testname);
+/* Return 0 if result is equal to not_expected_result, else return 1.
+ * Also update the global gTestSuccess flag if test fails. */
+int TEST_NEQ(int result, int not_expected_result, char* testname);
 
 /* Test firmware image generation functions. */
 FirmwareImage* GenerateTestFirmwareImage(int algorithm,