scripts: mxsimage: Allow unencrypted images ...

Normally MXS SoCs only allow to boot images which have been
encrypted with a zero key. If the ENABLE_UNENCTRYPTED_BOOT fuse
is blown then the SoC also allows to boot unencrypted images.
Add an option to the mxsimage tool to generate such images.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Roland Hieber <r.hieber@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

scripts: mxsimage: Fix build with OpenSSL < 1.1.x ...

Move the compatibility wrapper functions up so that they
are defined before they are used.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

scripts: mxsimage: Fix build with OpenSSL 1.1.x ...

The EVP_MD_CTX and EVP_CIPHER_CTX are made opaque since 1.1.x , so instead
of embedding them directly into struct sb_image_ctx and initializing them
using EVP_*_CTX_init(), we use pointers and allocate the crypto contexts
using EVP_*_CTX_new().

This is an adoption of the U-Boot commit 7bae13b7579a6b from Marek Vasut

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

scripts: mxs: Use Kernel includes ...

Use the common definition of ARRAY_SIZE and roundup.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

scripts: add mxsimage tool ...

This is copied from U-Boot v2014.10 and modified for use with
barebox:

- Add a main() function to make it a standalone tool
- Add option to pass in the prepare stage and bootloader
  image as options. If the config file contains @PREP@ or
  @BOOTLOADER@ the string will be replaced with the actual
  image file passed via the -p and -b options.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>