After-merge fix:

The declaration of "thr_client_alarm" had got lost, keep it in "mysys/thr_alarm.c".


mysys/thr_alarm.c:
  After-merge fix:
  In 4.1, the variable "thr_client_alarm" is declared in this module.

mysys/thr_alarm.c

@@ -36,6 +36,7 @@
 #define ETIME ETIMEDOUT
 #endif
 
+uint thr_client_alarm;
 static int alarm_aborted=1;			/* No alarm thread */
 my_bool thr_alarm_inited= 0;
 volatile my_bool alarm_thread_running= 0;