sbsign: name the input file when hashing it fails

verb_sign() logs argv[0], which is the verb, as the name of the file it
could not hash. Log argv[1], the input file.

(cherry picked from commit 9030bbfc90c646b7c07bbe8d70cfe7ba40b5a25a)

src/sbsign/sbsign.c

@@ -481,7 +481,7 @@ static int verb_sign(int argc, char *argv[], uintptr_t _data, void *userdata) {
         size_t pehashsz;
         r = pe_hash(srcfd, sym_EVP_sha256(), &pehash, &pehashsz);
         if (r < 0)
-                return log_error_errno(r, "Failed to hash PE binary %s: %m", argv[0]);
+                return log_error_errno(r, "Failed to hash PE binary %s: %m", argv[1]);
 
         _cleanup_free_ uint8_t *idcraw = NULL;
         size_t idcrawsz = 0; /* avoid false maybe-uninitialized warning */