u-boot: fit: add support to decrypt fit with aes

This commit add to u-boot the support to decrypt
fit image encrypted with aes. The FIT image contains
the key name and the IV name. Then u-boot look for
the key and IV in his device tree and decrypt images
before moving to the next stage.

Signed-off-by: Philippe Reynes <philippe.reynes@softathome.com>
diff --git a/lib/aes/Makefile b/lib/aes/Makefile
new file mode 100644
index 0000000..daed52a
--- /dev/null
+++ b/lib/aes/Makefile
@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Copyright (c) 2019, Softathome
+
+obj-$(CONFIG_$(SPL_)FIT_CIPHER) += aes-decrypt.o