exec: drop useless #if

This code is only compiled for softmmu targets.

Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

exec.c

@@ -1430,10 +1430,8 @@ static void notdirty_mem_write(void *opaque, hwaddr ram_addr,
     int dirty_flags;
     dirty_flags = cpu_physical_memory_get_dirty_flags(ram_addr);
     if (!(dirty_flags & CODE_DIRTY_FLAG)) {
-#if !defined(CONFIG_USER_ONLY)
         tb_invalidate_phys_page_fast(ram_addr, size);
         dirty_flags = cpu_physical_memory_get_dirty_flags(ram_addr);
-#endif
     }
     switch (size) {
     case 1: