Use natural-sized integer field for tcb::flags

* defs: Change struct tcb::flags type from short to int.
This results in smaller code at least on x86.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
diff --git a/defs.h b/defs.h
index 80c8c83..1542861 100644
--- a/defs.h
+++ b/defs.h
@@ -387,7 +387,7 @@
 
 /* Trace Control Block */
 struct tcb {
-	short flags;		/* See below for TCB_ values */
+	int flags;		/* See below for TCB_ values */
 	int pid;		/* Process Id of this entry */
 	long scno;		/* System call number */
 	int u_nargs;		/* System call arguments */