binderfs: binderfs_test: remove unused variable

The variable "wret" is never referenced in the code, just remove it.

Signed-off-by: Ba Jing <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

tools/testing/selftests/filesystems/binderfs/binderfs_test.c

···
 {
 	int fd, ret, saved_errno, result = 1;
 	size_t len;
-	ssize_t wret;
 	struct binderfs_device device = { 0 };
 	struct binder_version version = { 0 };
 	char binderfs_mntpt[] = P_tmpdir "/binderfs_XXXXXX",