serial-parsers,port-serial-at: move echo removal into serial parser

Mainly because we need somewhere to stash the call end regex, and
it's silly to have a 3rd instance of that in MMPortSerialAt when
we already have one in the serial parsers that MMPortSerialAt
relies on pretty heavily.

Signed-off-by: Dan Williams <dan@ioncontrol.co>

src/tests/test-at-serial-port.c

@@ -89,6 +89,7 @@ at_serial_echo_removal (void)
     guint i;
 
     for (i = 0; i < G_N_ELEMENTS (echo_removal_tests); i++) {
+        gpointer    parser;
         GByteArray *ba;
 
         /* Note that we add last NUL also to the byte array, so that we can compare
@@ -98,7 +99,9 @@ at_serial_echo_removal (void)
                               (guint8 *)echo_removal_tests[i].original,
                               strlen (echo_removal_tests[i].original) + 1);
 
-        mm_port_serial_at_remove_echo (ba);
+        parser = mm_serial_parser_v1_new ();
+        mm_serial_parser_v1_remove_echo (parser, ba);
+        mm_serial_parser_v1_destroy (parser);
 
         g_assert_cmpstr ((gchar *)ba->data, ==, echo_removal_tests[i].without_echo);
 
@@ -119,6 +122,7 @@ _run_parse_test (const ParseResponseTest tests[], guint number_of_tests)
         parser = mm_serial_parser_v1_new ();
         response = g_string_new (tests[i].response);
         found = mm_serial_parser_v1_parse (parser, response, NULL, &error);
+        mm_serial_parser_v1_destroy (parser);
 
         /* Verify if we expect a match or not */
         g_assert_cmpint (found, ==, tests[i].found);