test: fuzz: Add framework for fuzzing

Add the basic infrastructure for declaring fuzz tests and a command to
invoke them.

Signed-off-by: Andrew Scull <ascull@google.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/test/fuzz/Makefile b/test/fuzz/Makefile
new file mode 100644
index 0000000..03eeeeb
--- /dev/null
+++ b/test/fuzz/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Copyright (c) 2022 Google, Inc.
+# Written by Andrew Scull <ascull@google.com>
+#
+
+obj-$(CONFIG_$(SPL_)CMDLINE) += cmd_fuzz.o