media: drxj: get rid of uneeded casts

Instead of doing casts, use %zd to print sizes, in order to make
smatch happier:
	drivers/media/dvb-frontends/drx39xyj/drxj.c:11814 drx_ctrl_u_code() warn: argument 4 to %u specifier is cast from pointer
	drivers/media/dvb-frontends/drx39xyj/drxj.c:11845 drx_ctrl_u_code() warn: argument 3 to %u specifier is cast from pointer
	drivers/media/dvb-frontends/drx39xyj/drxj.c:11869 drx_ctrl_u_code() warn: argument 3 to %u specifier is cast from pointer
	drivers/media/dvb-frontends/drx39xyj/drxj.c:11878 drx_ctrl_u_code() warn: argument 3 to %u specifier is cast from pointer

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