Add MBEDTLS_PSA_HAS_ITS_IO to config.pl exclude list

diff --git a/scripts/config.pl b/scripts/config.pl
index 89fd885..18e1dc8 100755
--- a/scripts/config.pl
+++ b/scripts/config.pl
@@ -43,6 +43,7 @@
 #   MBEDTLS_PSA_CRYPTO_STORAGE_FILE_C
 #   MBEDTLS_PSA_CRYPTO_STORAGE_ITS_C
 #   MBEDTLS_PSA_CRYPTO_SPM
+#   MBEDTLS_PSA_HAS_ITS_IO
 #   and any symbol beginning _ALT
 #
 
@@ -109,6 +110,7 @@
 MBEDTLS_PSA_CRYPTO_STORAGE_FILE_C
 MBEDTLS_PSA_CRYPTO_STORAGE_ITS_C
 MBEDTLS_PSA_CRYPTO_SPM
+MBEDTLS_PSA_HAS_ITS_IO
 _ALT\s*$
 );