lib/safe_file_ops: print file info when file_lines_scanf parsed fail

Signed-off-by: Yang Xu <xuyang2018.jy@cn.fujitsu.com>
Reviewed-by: Cyril Hrubis <chrubis@suse.cz>
diff --git a/lib/safe_file_ops.c b/lib/safe_file_ops.c
index b576cb9..e06d399 100644
--- a/lib/safe_file_ops.c
+++ b/lib/safe_file_ops.c
@@ -217,7 +217,7 @@
 
 	if (strict && ret != arg_count) {
 		tst_brkm(TBROK, cleanup_fn, "Expected %i conversions got %i"
-			" at %s:%d", arg_count, ret, file, lineno);
+			" FILE '%s' at %s:%d", arg_count, ret, path, file, lineno);
 		return 1;
 	}