[hurd,commited] tst-backtrace5: Fix on hurd

hurd has intermediate io_read and read_nocancel functions, skip them down to
the actual read call from the test.
---
 debug/tst-backtrace5.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/debug/tst-backtrace5.c b/debug/tst-backtrace5.c
index 6538da9ab5..75a018670a 100644
--- a/debug/tst-backtrace5.c
+++ b/debug/tst-backtrace5.c
@@ -77,9 +77,9 @@ handle_signal (int signum)
 
   /* Skip the signal trampoline and any cancellable syscall wrapper frames
      (__syscall_cancel*) and require the read syscall wrapper to be
-     present.  */
+     present (but skip intermediates).  */
   for (i = 1; i < n; i++)
-    if (match (symbols[i], "read"))
+    if (match (symbols[i], "read") && !match (symbols[i], "read_nocancel") && !match (symbols[i], "io_read"))
       break;
   if (i == n)
     {
-- 
2.53.0