Revert an accidentally flipped prediction.

PiperOrigin-RevId: 795678986
diff --git a/centipede/sancov_interceptors.cc b/centipede/sancov_interceptors.cc
index 47b9cd1..60a7090 100644
--- a/centipede/sancov_interceptors.cc
+++ b/centipede/sancov_interceptors.cc
@@ -208,7 +208,7 @@
     const pthread_attr_t *absl_nullable attr,  // NOLINT
     void *(*start_routine)(void *),
     void *absl_nullable arg) {  // NOLINT
-  if (ABSL_PREDICT_TRUE(!tls.started)) {
+  if (ABSL_PREDICT_FALSE(!tls.started)) {
     return REAL(pthread_create)(thread, attr, start_routine, arg);
   }
   // Wrap the arguments. Will be deleted in MyThreadStart.