package: various fixes for syntax-check

* cfg.mk: Disable checks where needed (e.g., we do want to check the
behavior with tabs).
(sc_at_parser_check): Remove.  Unfortunately since
a11c144609 we no longer use the './'
prefix to run programs in the current directory.  That was so that we
could run Java programs like the other, although they are no run with
the `./` prefix (see 967a59d2c0).
As a consequence this sc check no longer makes sense.
However, since now AT_PARSER_CHECK passes the `./` prefix itself, this
sc-check was superfluous.
* examples/c/reccalc/scan.l: Use memcpy, not strncpy.
* src/ielr.c, src/reader.c: Obfuscate "lr(0)" so that the sc-check for
"space before paren" does not fire.
* tests/diagnostics.at: Avoid space-tab, use tab-tab.

src/ielr.c

@@ -50,7 +50,7 @@ lr_type_get (void)
 {
   char *type = muscle_percent_define_get ("lr.type");
   LrType res;
-  if (STREQ (type, "lr(0)"))
+  if (STREQ (type, "lr""(0)"))
     res = LR_TYPE__LR0;
   else if (STREQ (type, "lalr"))
     res = LR_TYPE__LALR;

src/reader.c

@@ -763,7 +763,7 @@ prepare_percent_define_front_end_variables (void)
   {
     static char const * const values[] =
       {
-       "lr.type", "lr(0)", "lalr", "ielr", "canonical-lr", NULL,
+       "lr.type", "lr""(0)", "lalr", "ielr", "canonical-lr", NULL,
        "lr.default-reduction", "most", "consistent", "accepting", NULL,
        NULL
       };