scripts/kernel-doc: Do not track section counter across processed files

BugLink: https://bugs.launchpad.net/bugs/2101915

[ Upstream commit be9264110e4e874622d588a75daf930539fdf6ea ]

The section counter tracks how many sections of kernel-doc were added.
The only real use of the counter value is to check if anything was
actually supposed to be output and give a warning is nothing is
available.

The current logic of remembering the initial value and then resetting
the value then when processing each file means that if a file has the
same number of sections as the previously processed one, a warning is
incorrectly given.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20241008082905.4005524-1-wenst@chromium.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Koichiro Den <koichiro.den@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

scripts/kernel-doc

@@ -2312,7 +2312,6 @@ sub process_inline($$) {
 
 sub process_file($) {
     my $file;
-    my $initial_section_counter = $section_counter;
     my ($orig_file) = @_;
 
     $file = map_filename($orig_file);
@@ -2350,8 +2349,7 @@ sub process_file($) {
     }
 
     # Make sure we got something interesting.
-    if ($initial_section_counter == $section_counter && $
-        output_mode ne "none") {
+    if (!$section_counter && $output_mode ne "none") {
         if ($output_selection == OUTPUT_INCLUDE) {
             emit_warning("${file}:1", "'$_' not found\n")
                 for keys %function_table;