more trivial signedness fixes in drivers

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index 28d1457..55c3237 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -3101,7 +3101,7 @@
 	int i;
 	int listlength = 0;
 	__u32 lunid = 0;
-	int block_size;
+	unsigned block_size;
 	sector_t total_size;
 
 	ld_buff = kzalloc(sizeof(ReportLunData_struct), GFP_KERNEL);