Add fuzz testing driver programs for kernel and firmware verification.

The driver programs are useful in quick and dirty fuzz testing of the verification code with blind smartfuzzers like Bunny (http://code.google.com/p/bunny-the-fuzzer/).

Also fixes a bug with image generation in kernel_utility.

Tests: All existing tests still pass. VerifyKernel() and VerifyFirmware() can successfully verify images generated by {firmware|kernel}_utility.

Review URL: http://codereview.chromium.org/975007

utils/kernel_image.c

@@ -404,6 +404,7 @@ int VerifyKernelHeader(const uint8_t* firmware_key_blob,
                                 kernel_sign_key_len),
                  FIELD_LEN(header_checksum))) {
     Free(header_checksum);
+    fprintf(stderr, "VerifyKernelHeader: Invalid header hash\n");
     return VERIFY_KERNEL_INVALID_IMAGE;
   }
   Free(header_checksum);