Remove warning with GCC 12 and TSan

Compiler is unhappy that the return from mbedtls_cipher_get_name() could
be NULL as this is used in a printf statement.

Signed-off-by: Paul Elliott <paul.elliott@arm.com>
diff --git a/programs/aes/crypt_and_hash.c b/programs/aes/crypt_and_hash.c
index 226718b..f15b85e 100644
--- a/programs/aes/crypt_and_hash.c
+++ b/programs/aes/crypt_and_hash.c
@@ -103,7 +103,14 @@
         list = mbedtls_cipher_list();
         while (*list) {
             cipher_info = mbedtls_cipher_info_from_type(*list);
-            mbedtls_printf("  %s\n", mbedtls_cipher_info_get_name(cipher_info));
+            if (cipher_info) {
+                const char *name = mbedtls_cipher_info_get_name(cipher_info);
+
+                if (name) {
+                    mbedtls_printf("  %s\n", mbedtls_cipher_info_get_name(cipher_info));
+                }
+            }
+
             list++;
         }