scanf: remove redundant debug logs

scanf: remove redundant debug logs

Remove `pr_debug` calls which emit information already contained in
`pr_warn` calls that occur on test failure. This reduces unhelpful test
verbosity.

Note that a `pr_debug` removed from `_check_numbers_template` appears to
have been the only guard against silent false positives, but in fact
this condition is handled in `_test`; it is only possible for `n_args`
to be `0` in `_check_numbers_template` if the test explicitly expects it
*and* `vsscanf` returns `0`, matching the expectation.

Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Link: https://lore.kernel.org/r/20250307-scanf-kunit-convert-v9-2-b98820fa39ff@gmail.com
Signed-off-by: Kees Cook <kees@kernel.org>