x86: set_personality_ia32() misses force_personality32

05d43ed8a "x86: get rid of the insane TIF_ABI_PENDING bit" forgot about
force_personality32.  Fix.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/x86/kernel/process_64.c

@@ -527,6 +527,7 @@ void set_personality_ia32(void)
 
 	/* Make sure to be in 32bit mode */
 	set_thread_flag(TIF_IA32);
+	current->personality |= force_personality32;
 
 	/* Prepare the first "return" to user space */
 	current_thread_info()->status |= TS_COMPAT;