accel/stubs: reduce headers from tcg-stub

We don't need much for these. However I do wonder why these aren't
just null inlines in exec-all.h

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

accel/stubs/tcg-stub.c

@@ -11,7 +11,6 @@
  */
 
 #include "qemu/osdep.h"
-#include "qemu-common.h"
 #include "cpu.h"
 #include "tcg/tcg.h"
 #include "exec/exec-all.h"