Fixed some issues found by valgrind

(one testcase, one memory leak and some accesses to not initialized memory)


mysql-test/r/events_scheduling.result:
  Changed event timer to two seconds to not get problems with slow system or when running with valgrind
mysql-test/t/events_scheduling.test:
  Changed event timer to two seconds to not get problems with slow system or when running with valgrind
mysql-test/valgrind.supp:
  Avoid purify warnings from DBUG library (safe to do)
sql/ha_berkeley.cc:
  Fix problem with not freed memory
sql/sql_class.cc:
  Ensure that row_count is initalized (as we otherwise may access it uninitialized)
sql/sql_show.cc:
  c_ptr -> ptr to avoid accessing not initialized memory
sql/sql_yacc.yy:
  Fix to not access not initialized memory
sql/table.cc:
  Fix to not access not initialized memory
sql/time.cc:
  Fix to not access not initialized memory

mysql-test/valgrind.supp

@@ -420,3 +420,16 @@
    fun:fprintf
    fun:print_stacktrace
 }
+
+#
+# Safe warnings, that may happen because of thread scheduling
+#
+
+{
+   dbug initialization
+   Memcheck:Leak
+   fun:malloc
+   fun:DbugMalloc
+   fun:ListAdd
+   fun:_db_set_
+}