at91bootstrap: upstream moved to another URL

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

boot/at91bootstrap/at91bootstrap.mk

@@ -4,7 +4,7 @@
 #
 #############################################################
 AT91BOOTSTRAP_VERSION = 1.16
-AT91BOOTSTRAP_SITE = http://www.atmel.com/dyn/resources/prod_documents/
+AT91BOOTSTRAP_SITE = http://www.atmel.com/Images
 AT91BOOTSTRAP_SOURCE = AT91Bootstrap$(AT91BOOTSTRAP_VERSION).zip
 
 AT91BOOTSTRAP_BOARD = $(call qstrip,$(BR2_TARGET_AT91BOOTSTRAP_BOARD))