ppc64: Fix warnings

arch/ppc64/kernel/mk_defs.c

@@ -47,7 +47,6 @@ main(void)
 	DEFINE(THREAD_SHIFT, THREAD_SHIFT);
 	DEFINE(THREAD_SIZE, THREAD_SIZE);
 	DEFINE(TI_FLAGS, offsetof(struct thread_info, flags));
-	DEFINE(_TIF_32BIT, _TIF_32BIT);
 
 	/* task_struct->thread */
 	DEFINE(THREAD, offsetof(struct task_struct, thread));

arch/ppc64/kernel/process.c

@@ -298,8 +298,6 @@ int sys_execve(unsigned long a0, unsigned long a1, unsigned long a2,
 
 void initialize_paca_hardware_interrupt_stack(void)
 {
-	extern struct naca_struct *naca;
-
 	int i;
 	unsigned long stack;
 	unsigned long end_of_stack =0;