log: avoid regressions for relative log paths

src/lxc/confile.c

@@ -1597,9 +1597,6 @@ static int set_config_log_file(const char *key, const char *value,
 		return 0;
 	}
 
-	if (!abspath(value))
-		return ret_errno(EINVAL);
-
 	/*
 	 * Store these values in the lxc_conf, and then try to set for actual
 	 * current logging.

src/lxc/log.c

@@ -492,9 +492,6 @@ static int build_dir(const char *name)
 	if (is_empty_string(name))
 		return ret_errno(EINVAL);
 
-	if (!abspath(name))
-		return ret_errno(EINVAL);
-
 	/* Make copy of the string since we'll be modifying it. */
 	n = strdup(name);
 	if (!n)