iowatcher: Properly initialize trace.name in find_trace_file

Signed-off-by: Chris Mason <clm@fb.com>
diff --git a/iowatcher/blkparse.c b/iowatcher/blkparse.c
index 83e707a..ef33d5b 100644
--- a/iowatcher/blkparse.c
+++ b/iowatcher/blkparse.c
@@ -875,7 +875,7 @@
 	 */
 	dot = strrchr(filename, '.');
 	if (!dot || strcmp(".dump", dot) != 0) {
-		struct tracelist trace = {0};
+		struct tracelist trace = {0 ,NULL};
 		if (dot && dot != filename)
 			len = dot - filename;