[PATCH] tests/tcg/multiarch: remove unused variable in linux-test

[Mukilan Thiyagarajan]

LLVM 15.0.0 has improved diagnostics for the
'nounused-but-set-variable' warning and now warns when
a variable is modified using pre/post increment/decrement
operators but is otherwise never read.

linux-tests.c has such an unused variable 'wcount' and since
TCG tests are compiled with -Wall -Werror, this is causing
'make check-tcg' to fail when using LLVM 15.0.0 and above:

```
qemu/tests/tcg/multiarch/linux/linux-test.c:335:9:
error: variable 'wcount' set but not used [-Werror,-Wunused-but-set-variable]
    int wcount, rcount;
        ^
1 error generated.
Makefile:119: recipe for target 'linux-test' failed
```

This patch simply removes the 'wcount' variable as it
doesn't appear to impact the semantics of the test.
The WCOUNT_MAX constant is also renamed to RCOUNT_MAX to
better reflect the usage.
---
 tests/tcg/multiarch/linux/linux-test.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/tests/tcg/multiarch/linux/linux-test.c 
b/tests/tcg/multiarch/linux/linux-test.c
index 5a2a4f2258..35540dc357 100644
--- a/tests/tcg/multiarch/linux/linux-test.c
+++ b/tests/tcg/multiarch/linux/linux-test.c
@@ -325,19 +325,18 @@ static void test_socket(void)
     chk_error(close(server_fd));
 }
 
-#define WCOUNT_MAX 512
+#define RCOUNT_MAX 512
 
 static void test_pipe(void)
 {
     fd_set rfds, wfds;
     int fds[2], fd_max, ret;
     uint8_t ch;
-    int wcount, rcount;
+    int rcount;
 
     chk_error(pipe(fds));
     chk_error(fcntl(fds[0], F_SETFL, O_NONBLOCK));
     chk_error(fcntl(fds[1], F_SETFL, O_NONBLOCK));
-    wcount = 0;
     rcount = 0;
     for(;;) {
         FD_ZERO(&rfds);
@@ -354,13 +353,12 @@ static void test_pipe(void)
             if (FD_ISSET(fds[0], &rfds)) {
                 chk_error(read(fds[0], &ch, 1));
                 rcount++;
-                if (rcount >= WCOUNT_MAX)
+                if (rcount >= RCOUNT_MAX)
                     break;
             }
             if (FD_ISSET(fds[1], &wfds)) {
                 ch = 'a';
                 chk_error(write(fds[1], &ch, 1));
-                wcount++;
             }
         }
     }
-- 
2.17.1