Use a script to update DEBUG macro invocations to use it as a variadic
macro, supplying format string and its arguments directly, instead of
wrapping them in parens.

This script was used to update the code:

grep -rwl --include '*.[hc]' DEBUG . |
    while read f; do
        mv "$f"{,.orig}
        perl -e \
            'use strict;
             use File::Slurp;
             my $text=read_file(\*STDIN);
             $text=~s#(\bDEBUG\s*\([^(]+)\((.*?)\)\s*\)\s*;#$1$2);#gs;
             print $text;' < "$f.orig" > "$f"
        rm "$f.orig"
    done

Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>
Reviewed-by: Stephen Gallagher <sgallagh@redhat.com>
Reviewed-by: Simo Sorce <simo@redhat.com>

Return EINVAL if number of tries is <= 0. Also the parameter
retries was renamed to num_tries, so it is more obvious that
it also includes the first try.