accel/tcg: Remove dead code

The global cpu_single_env variable has been removed more than 5 years
ago, so apparently nobody used this dead debug code in that timeframe
anymore. Thus let's remove it completely now.
Signed-off-by: NThomas Huth <thuth@redhat.com>
Message-Id: <1537204134-15905-1-git-send-email-thuth@redhat.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

accel/tcg/translate-all.c

@@ -2009,15 +2009,6 @@ void tb_invalidate_phys_page_fast(struct page_collection *pages,
 {
     PageDesc *p;
 
-#if 0
-    if (1) {
-        qemu_log("modifying code at 0x%x size=%d EIP=%x PC=%08x\n",
-                  cpu_single_env->mem_io_vaddr, len,
-                  cpu_single_env->eip,
-                  cpu_single_env->eip +
-                  (intptr_t)cpu_single_env->segs[R_CS].base);
-    }
-#endif
     assert_memory_lock();
 
     p = page_find(start >> TARGET_PAGE_BITS);