Clean up some duplicated prototype declarations.
Get rid of now useless AVR32 initcalls.h file.

Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Albert Aribaud <albert.aribaud@free.fr>
Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Graeme Russ <graeme.russ@gmail.com>