fitimage.bbclass: make engine parameters in FITIMAGE_MKIMAGE_EXTRA_ARGS fail early

Now that oe-core moved to OpenSSL 4.0, the engine API is gone.
As a result uboot-mkimage's -N/--engine no longer work:

  Failed to sign 'signature-1' signature node in 'conf-imx6dl-riotboard.dtb' conf node
  uboot-mkimage Can't add hashes to FIT blob: -1
  Error: Bad parameters for FIT image type
  Usage: uboot-mkimage [-T type] -l image
            -l ==> list image header information
            -T ==> parse image file as 'type'
            -q ==> quiet

A previous patch documented how provider-based PKCS#11 signing works.
Now make an engine option in FITIMAGE_MKIMAGE_EXTRA_ARGS a fatal error. It
has no effect anymore, so a recipe still setting it has not been
migrated; failing with a clear message beats mkimage's generic error
messages above.

Signed-off-by: Bastian Krause <bst@pengutronix.de>
Signed-off-by: Khem Raj <khem.raj@oss.qualcomm.com>

meta-oe/classes/fitimage.bbclass

@@ -519,6 +519,11 @@ do_configure[postfuncs] += "write_manifest"
 
 do_fitimage () {
     if [ "${FITIMAGE_SIGN}" = "1" ]; then
+        case " ${FITIMAGE_MKIMAGE_EXTRA_ARGS} " in
+        *" --engine "*|*" --engine="*|*" -N "*)
+            bbfatal "FITIMAGE_MKIMAGE_EXTRA_ARGS: OpenSSL engines are no longer supported, see updated usage in fitimage.bbclass."
+            ;;
+        esac
         uboot-mkimage ${FITIMAGE_MKIMAGE_EXTRA_ARGS} \
             -k "${FITIMAGE_SIGN_KEYDIR}" -r \
             -f "${B}/manifest.its" \