soc/intel/braswell/romstage: Drop unused 'include <rtc.h>'

Change-Id: I6577d9a31da44be5b57bb10497d9bd02fc9bbcd3
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/31946
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>

src/soc/intel/braswell/romstage/romstage.c

@@ -43,7 +43,6 @@
 #include <soc/smm.h>
 #include <soc/spi.h>
 #include <build.h>
-#include <rtc.h>
 #include <pc80/mc146818rtc.h>
 
 void program_base_addresses(void)