ETRAX: Removed unused struct entry and fixed Windows build.

"struct timeval last" caused a compilation error with mingw32
(missing header for struct timeval).

It is unused, so it was possible to remove it.
Acked-by: NEdgar E. Iglesias <edgar.iglesias@gmail.com>
Signed-off-by: NStefan Weil <weil@mail.berlios.de>

hw/etraxfs_timer.c

@@ -52,7 +52,6 @@ struct etrax_timer {
     ptimer_state *ptimer_t0;
     ptimer_state *ptimer_t1;
     ptimer_state *ptimer_wd;
-    struct timeval last;
 
     int wd_hits;