uboot-imx

AVR32: Include <div64.h> instead of <asm/div64.h>

include/asm-avr32/div64.h was recently moved to include/div64.h, but
cpu/at32ap/interrupts.c wasn't properly updated (an earlier version of
the patch was merged perhaps?)

This patch updates cpu/at32ap/interrupts.c so that the avr32 port
compiles again.

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>