vboot: Add flag to vbutil_kernel for reconstruction of vmlinuz image

Adding functionality to allow for rebuilding of vmlinuz after it
has been processed into vblock and header stripped.  Basically appends
the 16-bit header of a vmlinuz image onto the end of the vblock.
BUG=chromium:438302
BRANCH=none
TEST=Successfully ran "make runalltests".
     Also, ran:
     1. Repack kernel block (so that 16-bit header is included):
        "vbutil_kernel --pack kern_0 ..."
     2. Verify kernel: "vbutil_kernel --verify kern_0 ... ".  This should
        be done before booting into kernel, but not necessary for it to work.
     3. Rebuild vmlinuz image:
        "vbutil_kernel --get-vmlinuz kern_0 --vmlinuz-out vm.out"
     4. Set up kexec with vmlinuz (this should complete with no errors):
        "kexec -l vm.out (other kernel cmd line args)"
     5. Boot into kernel:
        "kexec -e"

Change-Id: Iaa1582a1aedf70b43cdb3a56cde1fb248f1793d4
Signed-off-by: Shelley Chen <shchen@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/232750
Reviewed-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-by: Randall Spangler <rspangler@chromium.org>
diff --git a/tests/vboot_common_tests.c b/tests/vboot_common_tests.c
index 7cfea90..8fd021a 100644
--- a/tests/vboot_common_tests.c
+++ b/tests/vboot_common_tests.c
@@ -31,7 +31,7 @@
 	TEST_EQ(EXPECTED_VBFIRMWAREPREAMBLEHEADER2_1_SIZE,
 		sizeof(VbFirmwarePreambleHeader),
 		"sizeof(VbFirmwarePreambleHeader)");
-	TEST_EQ(EXPECTED_VBKERNELPREAMBLEHEADER_SIZE,
+	TEST_EQ(EXPECTED_VBKERNELPREAMBLEHEADER2_1_SIZE,
 		sizeof(VbKernelPreambleHeader),
 		"sizeof(VbKernelPreambleHeader)");