unisys: remove the thread variable and API

remove the should_stop variable and KILL API as they are
no longer required

Cc: Ken Cox <jkc@redhat.com>
Cc: Benjamin Romer <benjamin.romer@unisys.com>
Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Benjamin Romer <benjamin.romer@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/unisys/include/uisthread.h

@@ -27,7 +27,6 @@
 struct uisthread_info {
 	struct task_struct *task;
 	int id;
-	int should_stop;
 	struct completion has_stopped;
 };
 

drivers/staging/unisys/uislib/uisthread.c

@@ -24,8 +24,6 @@
 #include "uisutils.h"
 #include "uisthread.h"
 
-#define KILL(a, b, c) kill_pid(find_vpid(a), b, c)
-
 /* this is shorter than using __FILE__ (full path name) in
  * debug/info/error messages
  */