authvar: Remove unreachable free()

[cpackham-atlnz]

When building using GCC 15 the following error is hit

  authvar.c: In function 'main':
  authvar.c:450:17: error: 'free' called on a pointer to an unallocated object '"NSS Certificate DB"' [-Werror=free-nonheap-object]
    450 |                 free(tokenname);
        |                 ^
  authvar.c:270:15: note: assigned here
    270 |         char *tokenname = "NSS Certificate DB";
        |               ^
  lto1: all warnings being treated as errors
  lto-wrapper: fatal error: gcc returned 1 exit status

This might be a false positive since the tokenname != origtoken condition should never be satisfied but it might also be an indication that lto or other optimisations have elided some code that they shouldn't have. Regardless tokenname is allocated on the stack and never modified so the call to free() and the origtoken local aren't needed and can be dropped.

[cpackham-atlnz]

I first hit this with pesign-113 which ONIE packages. I can't reproduce the original error with pesign/main on fedora:rawhide as I suspect the optimization behaviour may have changed (there are certainly some cflags changes between 113 and main). Nevertheless the code is still unreachable so removing it is probably still a good idea.