MINOR: resolvers: move the resolv.conf parser in parse_resolv_conf()

Move the resolv.conf parser from the cfg_parse_resolvers so it could be
used separately.

Some changes were made in the memprintf in order to use a char **
instead of a char *. Also the variable is tested before each memprintf
so could skip them if no warnmsg nor errmsg were set.
1 file changed