qemu-char: fix warning 'res' may be used uninitialized

Signed-off-by: NIgor Mammedov <imammedo@redhat.com>
Message-id: 1403683241-20678-1-git-send-email-imammedo@redhat.com
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NStefan Weil <sw@weilnetz.de>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

qemu-char.c

@@ -132,7 +132,7 @@ int qemu_chr_fe_write(CharDriverState *s, const uint8_t *buf, int len)
 int qemu_chr_fe_write_all(CharDriverState *s, const uint8_t *buf, int len)
 {
     int offset = 0;
-    int res;
+    int res = 0;
 
     qemu_mutex_lock(&s->chr_write_lock);
     while (offset < len) {