drbd: silence underflow warning in read_in_block()

My static checker warns that "data_size" could be negative and underflow
the limit check.  The code looks suspicious but I don't know if it is a
real bug.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
diff --git a/include/linux/drbd.h b/include/linux/drbd.h
index 20ec890..debb70d 100644
--- a/include/linux/drbd.h
+++ b/include/linux/drbd.h
@@ -52,7 +52,7 @@
 #endif
 
 extern const char *drbd_buildtag(void);
-#define REL_VERSION "8.4.3"
+#define REL_VERSION "8.4.5"
 #define API_VERSION 1
 #define PRO_VERSION_MIN 86
 #define PRO_VERSION_MAX 101