ARC: Setup Vector Table Base in early boot

Otherwise early boot exceptions such as instructions errors due to
configuration mismatch between kernel and hardware go off to la-la land,
as opposed to hitting the handler and panic()'ing properly.

Signed-off-by: Vineet Gupta <[e-mail]>

arch/arc/kernel/head.S

···
 	; Don't clobber r0-r4 yet. It might have bootloader provided info
 	;-------------------------------------------------------------------
 
+	sr	@_int_vec_base_lds, [AUX_INTR_VEC_BASE]
+
 #ifdef CONFIG_SMP
 	; Only Boot (Master) proceeds. Others wait in platform dependent way
 	;	IDENTITY Reg [ 3  2  1  0 ]

arch/arc/kernel/irq.c

···
 {
 	int level_mask = 0;
 
-	write_aux_reg(AUX_INTR_VEC_BASE, _int_vec_base_lds);
-
 	/* Disable all IRQs: enable them as devices request */
 	write_aux_reg(AUX_IENABLE, 0);