check-names: also check PSA files

Allow both mbedtls and psa identifiers in either set of files for now.
diff --git a/tests/scripts/check-names.sh b/tests/scripts/check-names.sh
index 4c66440..68493f9 100755
--- a/tests/scripts/check-names.sh
+++ b/tests/scripts/check-names.sh
@@ -53,7 +53,7 @@
 for THING in identifiers; do
     printf "Names of $THING: "
     test -r $THING
-    BAD=$( grep -v '^mbedtls_[0-9a-z_]*[0-9a-z]$' $THING || true )
+    BAD=$( grep -E -v '^(mbedtls|psa)_[0-9a-z_]*[0-9a-z]$' $THING || true )
     if [ "x$BAD" = "x" ]; then
         echo "PASS"
     else