Bug#26536 func_time failure on vm-win2003-64-b, occurs every time

 - Fixes for 5.1
 - Always use long for my_time_t


include/my_time.h:
  Use long for my_time_t
  It should be signed and hold seconds for 1902 -- 2038-01-19 range
  i.e at least a 32bit variable
  
  Using the system built in time_t is not an option as
  we rely on the above requirements in the time functions
  
  For example QNX has an unsigned time_t type

include/my_time.h

@@ -38,13 +38,7 @@ extern uchar days_in_month[];
 
   For example QNX has an unsigned time_t type
 */
-#if defined(_WIN64) || defined(WIN64)
-/* on Win64 long is still 4 bytes (not 8!) */
-typedef LONG64 my_time_t;
-#else
-typedef time_t my_time_t;
-
-#endif
+typedef long my_time_t;
 
 #define MY_TIME_T_MAX LONG_MAX
 #define MY_TIME_T_MIN LONG_MIN