cpu/intel/haswell: Fix undefined behavior

Fix undefined behavior found by clang's -Wshift-sign-overflow. Left
shifting an int where the right operand is >= the width of the type
is undefined. Add UL suffix since it's safe for unsigned types.

Change-Id: Ieacf83d052bf4abfad639ef8e592bd8de17d16e6
Signed-off-by: Ryan Salsamendi <rsalsamendi@hotmail.com>
Reviewed-on: https://review.coreboot.org/20467
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-by: Philipp Deppenwiese <zaolin.daisuki@gmail.com>
1 file changed