src: fix stray fprintf() calls, make checksrc verify

Replace with `ssh2_deb()`.

Also:
- adjust checksrc options to verify.
- checksrc-all.pl: fix an issue preventing picking up `tests/.checksrc`.

Follow-up to c090b696c6 #1556
Follow-up to af1e591eee #796

Closes #1997

scripts/checksrc-all.pl

@@ -20,7 +20,6 @@ my @options = (
     "-aCreateFileA",
     "-afclose",
     "-afopen",
-    "-afprintf",
     "-afree",
     "-afstat",
     "-amalloc",
@@ -60,7 +59,7 @@ my $anyfailed = 0;
 for my $dir (@dirs) {
     if($is_git) {
         @files = ();
-        open(O, '-|', 'git', 'ls-files', "$dir/*.[ch]") || die; push @files, <O>; close(O);
+        open(O, '-|', 'git', 'ls-files', ":(glob)$dir/*.[ch]") || die; push @files, <O>; close(O);
         chomp(@files);
     }
     else {