Rename (and relabel) pkcs12 test case

Remove surplus _test suffix. Change labeling from Pcks12 to PCKS#12 as
it should be.

Signed-off-by: Paul Elliott <paul.elliott@arm.com>
diff --git a/tests/suites/test_suite_pkcs12.function b/tests/suites/test_suite_pkcs12.function
index 6f49faf..3d402d7 100644
--- a/tests/suites/test_suite_pkcs12.function
+++ b/tests/suites/test_suite_pkcs12.function
@@ -16,10 +16,10 @@
  */
 
 /* BEGIN_CASE */
-void pkcs12_derive_key_test( int md_type, int key_size_arg,
-                             data_t *password_arg, int password_usage,
-                             data_t *salt_arg, int salt_usage,
-                             int iterations, int expected_status )
+void pkcs12_derive_key( int md_type, int key_size_arg,
+                        data_t *password_arg, int password_usage,
+                        data_t *salt_arg, int salt_usage,
+                        int iterations, int expected_status )
 
 {
    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;