[PATCH -next] intel_th: msu: Remove set but not used variable 'last'

[YueHaibing]

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/hwtracing/intel_th/msu.c: In function msc_win_switch:
drivers/hwtracing/intel_th/msu.c:1389:21: warning: variable last set but not 
used [-Wunused-but-set-variable]

It is never used since introduction in commit
aad14ad3cf3a ("intel_th: msu: Add current window tracking")

Signed-off-by: YueHaibing <yuehaib...@huawei.com>
---
 drivers/hwtracing/intel_th/msu.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/hwtracing/intel_th/msu.c b/drivers/hwtracing/intel_th/msu.c
index 81bb54fa3ce8..33072ca5fc4d 100644
--- a/drivers/hwtracing/intel_th/msu.c
+++ b/drivers/hwtracing/intel_th/msu.c
@@ -1386,10 +1386,9 @@ static int intel_th_msc_init(struct msc *msc)
 
 static void msc_win_switch(struct msc *msc)
 {
-       struct msc_window *last, *first;
+       struct msc_window *first;
 
        first = list_first_entry(&msc->win_list, struct msc_window, entry);
-       last = list_last_entry(&msc->win_list, struct msc_window, entry);
 
        if (msc_is_last_win(msc->cur_win))
                msc->cur_win = first;
-- 
2.17.1