tf-a-stm32mp: force verbose hexdump for FIP encryption key

When TrustFence encryption is enabled, the TF-A recipe converts the
binary FIP encryption key to a hexadecimal string and passes it to the
TF-A build as ENC_KEY.

hexdump suppresses repeated output by default and emits '*' when it folds
duplicate data. If that happens while converting the key, the generated
ENC_KEY contains the '*' marker instead of the full hex string. The
malformed value then breaks the make command line, and make can interpret
the remaining key fragment as a target, failing for example with:

make ... ENC_KEY=13eb911dfcc316b1b99bbbbf10a7000c3055e863* 166d3c8c9cd6f888b720a9 all
make: *** No rule to make target '166d3c8c9cd6f888b720a9'.  Stop.

Use hexdump -v so every byte of the binary key is emitted and ENC_KEY is
always a complete, contiguous hex string.

https://onedigi.atlassian.net/browse/DEL-10115

Signed-off-by: Javier Viguera <javier.viguera@digi.com>

meta-digi-arm/dynamic-layers/stm-st-stm32mp/recipes-bsp/trusted-firmware-a/tf-a-stm32mp_2.10.bbappend

@@ -212,7 +212,7 @@ do_compile() {
                         # The encryption key is already available in hexadecimal format, so just extract it from file
                         encrypt_key="$(cat ${encrypt_key})"
                     else
-                        encrypt_key="$(hexdump -e '/1 "%02x"' ${encrypt_key})"
+                        encrypt_key="$(hexdump -ve '/1 "%02x"' "${encrypt_key}")"
                     fi
                     encrypt_extra_opt="ENC_KEY=${encrypt_key}"
             fi