media: staging: allegro: cleanup two warnings

Sparse complains about two issues when building with i386
and COMPILE_TEST:

	drivers/staging/media/allegro-dvt/allegro-core.c:1849:36: warning: constant 0xffffffff00000000UL is so big it is unsigned long long
	drivers/staging/media/allegro-dvt/allegro-core.c:865:24: error: incompatible types in comparison expression (different type sizes)

Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>