auto_update.c: Fix GCC 4.6 build warnings

Fix:
../common/auto_update.c: In function 'au_check_header_valid':
../common/auto_update.c:94:16: warning: variable 'checksum' set but not used [-Wunused-but-set-variable]
../common/auto_update.c: In function 'do_auto_update':
../common/auto_update.c:400:30: warning: variable 'got_ctrlc' set but not used [-Wunused-but-set-variable]

Signed-off-by: Stefan Roese <sr@denx.de>
1 file changed