log: fix memory leak in regexp level set

Fixes: a5279180f5 ("eal: change several log levels matching a regexp")
Cc: stable@dpdk.org

Signed-off-by: Ivan Malov <ivan.malov@oktetlabs.ru>
Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>
Acked-by: Olivier Matz <olivier.matz@6wind.com>

lib/librte_eal/common/eal_common_log.c

@@ -110,6 +110,8 @@ rte_log_set_level_regexp(const char *pattern, uint32_t level)
 			rte_logs.dynamic_types[i].loglevel = level;
 	}
 
+	regfree(&r);
+
 	return 0;
 }