target_request: fix warning, do not set local variable to value it already has

Change-Id: If29b0efdc326ee1ce4c07ec9d8777744d674f367
Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>
Reviewed-on: http://openocd.zylin.com/490
Tested-by: jenkins
Reviewed-by: Øyvind Harboe <oyvindharboe@gmail.com>

src/target/target_request.c

@@ -164,7 +164,6 @@ static int add_debug_msg_receiver(struct command_context *cmd_ctx, struct target
 	/* see if there's already a list */
 	if (*p) {
 		/* find end of linked list */
-		p = &target->dbgmsg;
 		while ((*p)->next)
 			p = &((*p)->next);
 		p = &((*p)->next);