Use UNUSED wherever applicable in derive_input tests
Exhaustivity check:
```
<tests/suites/test_suite_psa_crypto.data awk -F: '$1=="derive_input" { for (step=1; step<=3; step++) { if ($(4*step-1) == "0") { if ($(4*step) != "UNUSED" || $(4*step+1) != "\"\"" || $(4*step+2) != "UNUSED") print NR, step, $(4*step), $(4*step+1), $(4*step+2) } } }'
```
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/tests/suites/test_suite_psa_crypto.data b/tests/suites/test_suite_psa_crypto.data
index 9968cd1..550c99e 100644
--- a/tests/suites/test_suite_psa_crypto.data
+++ b/tests/suites/test_suite_psa_crypto.data
@@ -2779,19 +2779,19 @@
PSA key derivation: HKDF-SHA-256, good case, omitted salt
depends_on:PSA_WANT_ALG_HKDF:PSA_WANT_ALG_SHA_256
-derive_input:PSA_ALG_HKDF(PSA_ALG_SHA_256):0:0:"":UNUSED:PSA_KEY_DERIVATION_INPUT_SECRET:PSA_KEY_TYPE_DERIVE:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_SUCCESS:PSA_KEY_DERIVATION_INPUT_INFO:PSA_KEY_TYPE_NONE:"":PSA_SUCCESS:PSA_KEY_TYPE_NONE:PSA_SUCCESS
+derive_input:PSA_ALG_HKDF(PSA_ALG_SHA_256):0:UNUSED:"":UNUSED:PSA_KEY_DERIVATION_INPUT_SECRET:PSA_KEY_TYPE_DERIVE:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_SUCCESS:PSA_KEY_DERIVATION_INPUT_INFO:PSA_KEY_TYPE_NONE:"":PSA_SUCCESS:PSA_KEY_TYPE_NONE:PSA_SUCCESS
PSA key derivation: HKDF-SHA-256, good case, info first
depends_on:PSA_WANT_ALG_HKDF:PSA_WANT_ALG_SHA_256
-derive_input:PSA_ALG_HKDF(PSA_ALG_SHA_256):0:0:"":PSA_SUCCESS:PSA_KEY_DERIVATION_INPUT_INFO:PSA_KEY_TYPE_NONE:"":PSA_SUCCESS:PSA_KEY_DERIVATION_INPUT_SECRET:PSA_KEY_TYPE_DERIVE:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_SUCCESS:PSA_KEY_TYPE_NONE:PSA_SUCCESS
+derive_input:PSA_ALG_HKDF(PSA_ALG_SHA_256):0:UNUSED:"":UNUSED:PSA_KEY_DERIVATION_INPUT_INFO:PSA_KEY_TYPE_NONE:"":PSA_SUCCESS:PSA_KEY_DERIVATION_INPUT_SECRET:PSA_KEY_TYPE_DERIVE:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_SUCCESS:PSA_KEY_TYPE_NONE:PSA_SUCCESS
PSA key derivation: HKDF-SHA-256, good case, info after salt
depends_on:PSA_WANT_ALG_HKDF:PSA_WANT_ALG_SHA_256
-derive_input:PSA_ALG_HKDF(PSA_ALG_SHA_256):0:0:"":PSA_SUCCESS:PSA_KEY_DERIVATION_INPUT_SECRET:PSA_KEY_TYPE_DERIVE:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_SUCCESS:PSA_KEY_DERIVATION_INPUT_INFO:PSA_KEY_TYPE_NONE:"":PSA_SUCCESS:PSA_KEY_TYPE_NONE:PSA_SUCCESS
+derive_input:PSA_ALG_HKDF(PSA_ALG_SHA_256):0:UNUSED:"":UNUSED:PSA_KEY_DERIVATION_INPUT_SECRET:PSA_KEY_TYPE_DERIVE:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_SUCCESS:PSA_KEY_DERIVATION_INPUT_INFO:PSA_KEY_TYPE_NONE:"":PSA_SUCCESS:PSA_KEY_TYPE_NONE:PSA_SUCCESS
PSA key derivation: HKDF-SHA-256, good case, omitted salt, info first
depends_on:PSA_WANT_ALG_HKDF:PSA_WANT_ALG_SHA_256
-derive_input:PSA_ALG_HKDF(PSA_ALG_SHA_256):PSA_KEY_DERIVATION_INPUT_INFO:PSA_KEY_TYPE_NONE:"":PSA_SUCCESS:PSA_KEY_DERIVATION_INPUT_SECRET:PSA_KEY_TYPE_DERIVE:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_SUCCESS:0:0:"":UNUSED:PSA_KEY_TYPE_NONE:PSA_SUCCESS
+derive_input:PSA_ALG_HKDF(PSA_ALG_SHA_256):PSA_KEY_DERIVATION_INPUT_INFO:PSA_KEY_TYPE_NONE:"":PSA_SUCCESS:PSA_KEY_DERIVATION_INPUT_SECRET:PSA_KEY_TYPE_DERIVE:"0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b":PSA_SUCCESS:0:UNUSED:"":UNUSED:PSA_KEY_TYPE_NONE:PSA_SUCCESS
PSA key derivation: HKDF-SHA-256, good case, key output
depends_on:PSA_WANT_ALG_HKDF:PSA_WANT_ALG_SHA_256