cbfstool: Fix help display message

For arm64, the machine type is arm64 in cbfstool, however it was displayed as
aarch64 in help message. This patch corrects it.

BUG=None
BRANCH=None
TEST=None

Original-Change-Id: I0319907d6c9d136707ed35d6e9686ba67da7dfb2
Original-Signed-off-by: Furquan Shaikh <furquan@google.com>
Original-Reviewed-on: https://chromium-review.googlesource.com/204379
Original-Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Original-Tested-by: Furquan Shaikh <furquan@chromium.org>
(cherry picked from commit 1f5f4c853efac5d842147ca0373cf9b5dd9f0ad0)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>

Change-Id: I00f51f1d4a9e336367f0619910fd8eb965b69bab
Reviewed-on: http://review.coreboot.org/8144
Tested-by: build bot (Jenkins)
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>

util/cbfstool/cbfstool.c

@@ -590,7 +590,7 @@ static void usage(char *name)
 			"Updates the FIT table with microcode entries\n"
 	     "\n"
 	     "ARCHes:\n"
-	     "  aarch64, arm, x86\n"
+	     "  arm64, arm, x86\n"
 	     "TYPEs:\n", name, name
 	    );
 	print_supported_filetypes();