linux-user: Remove #if 0'd cpu_get_real_ticks() definition

Remove the cpu_get_real_ticks() definition from linux-user/main.c.
This has been disabled via #if 0 and unused since commit 1dce7c3c22
in 2006; the definitions we actually use are in qemu-timer.h.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>

linux-user/main.c

diff --git a/linux-user/main.c b/linux-user/main.c
index 1a1c661..e84a18c 100644
--- a/linux-user/main.c
+++ b/linux-user/main.c
@@ -89,19 +89,6 @@
 }
 #endif
 
-/* timers for rdtsc */
-
-#if 0
-
-static uint64_t emu_time;
-
-int64_t cpu_get_real_ticks(void)
-{
-    return emu_time++;
-}
-
-#endif
-
 #if defined(CONFIG_USE_NPTL)
 /***********************************************************/
 /* Helper routines for implementing atomic operations.  */