Fix compilation warnings in dlz_wildcard_dynamic.c

Fix compilation warnings in dlz_wildcard_dynamic.c

    dlz_wildcard_dynamic.c: In function ‘dlz_lookup’:
    dlz_wildcard_dynamic.c:227:14: warning: variable ‘origin’ set but not used [-Wunused-but-set-variable]
      227 |         bool origin = true;
          |              ^~~~~~
    dlz_wildcard_dynamic.c: In function ‘dlz_lookup’:
    dlz_wildcard_dynamic.c:252:28: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
      252 |                 cd->record = "@";
          |                            ^
    dlz_wildcard_dynamic.c: In function ‘dlz_authority’:
    dlz_wildcard_dynamic.c:328:22: warning: unused variable ‘origin’ [-Wunused-variable]
      328 |                 bool origin;
          |                      ^~~~~~
    dlz_wildcard_dynamic.c:312:25: warning: unused variable ‘name’ [-Wunused-variable]
      312 |         const char *p, *name = "@";
          |                         ^~~~
    dlz_wildcard_dynamic.c: In function ‘dlz_create’:
    dlz_wildcard_dynamic.c:441:23: warning: comparison of integer expressions of different signedness: ‘int’ and ‘unsigned int’ [-Wsign-compare]
      441 |         for (i = 4; i < argc; i += 4) {
          |                       ^

(cherry picked from commit 76c8c58d5472d70330187a88e7a7f8b206e3f1e6)