cbfstool: add aarch64 as a name

The aarch64 is not really an arm variant, it's sufficiently
different that it can be considered (for purposes of cbfs, certainly)
to be a new architecture.

Add a constant in cbfs.h and strings to correspond to it.
Note that with the new cbfstool support that we added earlier,
the actual use of aarch64 ELF files actually "just works" (at
least when tested earlier).

BUG=None
TEST=It builds an image for nyan, and no new code is added.
BRANCH=None

Change-Id: Ib4900900d99c9aae6eef858d8ee097709368c4d4
Reviewed-on: https://chromium-review.googlesource.com/180221
Reviewed-by: Stefan Reinauer <reinauer@chromium.org>
Commit-Queue: Ronald Minnich <rminnich@chromium.org>
Tested-by: Ronald Minnich <rminnich@chromium.org>

util/cbfstool/cbfs.h

@@ -41,6 +41,7 @@ struct cbfs_header {
 #define CBFS_ARCHITECTURE_UNKNOWN  0xFFFFFFFF
 #define CBFS_ARCHITECTURE_X86      0x00000001
 #define CBFS_ARCHITECTURE_ARM      0x00000010
+#define CBFS_ARCHITECTURE_AARCH64  0x0000aa64
 
 #define CBFS_FILE_MAGIC "LARCHIVE"
 

util/cbfstool/cbfstool.c

@@ -520,7 +520,7 @@ static void usage(char *name)
 			"Updates the FIT table with microcode entries\n"
 	     "\n"
 	     "ARCHes:\n"
-	     "  arm, x86\n"
+	     "  aarch64, arm, x86\n"
 	     "TYPEs:\n", name, name
 	    );
 	print_supported_filetypes();

util/cbfstool/common.c

@@ -113,6 +113,7 @@ static struct {
 	uint32_t arch;
 	const char *name;
 } arch_names[] = {
+	{ CBFS_ARCHITECTURE_AARCH64, "aarch64" },
 	{ CBFS_ARCHITECTURE_ARM, "arm" },
 	{ CBFS_ARCHITECTURE_X86, "x86" },
 	{ CBFS_ARCHITECTURE_UNKNOWN, "unknown" }