make gpr_timespec platform agnostic
diff --git a/src/core/surface/channel_connectivity.c b/src/core/surface/channel_connectivity.c
index df2774b..cee1ddb 100644
--- a/src/core/surface/channel_connectivity.c
+++ b/src/core/surface/channel_connectivity.c
@@ -200,10 +200,10 @@
   GRPC_API_TRACE(
       "grpc_channel_watch_connectivity_state("
       "channel=%p, last_observed_state=%d, "
-      "deadline=gpr_timespec { tv_sec: %ld, tv_nsec: %d, clock_type: %d }, "
+      "deadline=gpr_timespec { tv_sec: %lld, tv_nsec: %d, clock_type: %d }, "
       "cq=%p, tag=%p)",
-      7, (channel, (int)last_observed_state, (long)deadline.tv_sec,
-          deadline.tv_nsec, (int)deadline.clock_type, cq, tag));
+      7, (channel, (int)last_observed_state, (long long)deadline.tv_sec,
+          (int)deadline.tv_nsec, (int)deadline.clock_type, cq, tag));
 
   grpc_cq_begin_op(cq);