Use gcc in test_psa_compliance

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index 1ac4d08..05d413b 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -3588,7 +3588,7 @@
     CC=gcc make -C library libmbedcrypto.a
 
     msg "unit test: test_psa_compliance.py"
-    ./tests/scripts/test_psa_compliance.py
+    CC=gcc ./tests/scripts/test_psa_compliance.py
 }
 
 support_test_psa_compliance () {