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

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Message-id: 1403683241-20678-1-git-send-email-imammedo@redhat.com
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
diff --git a/qemu-char.c b/qemu-char.c
index 2e50a10..f6bdf2f 100644
--- a/qemu-char.c
+++ b/qemu-char.c
@@ -132,7 +132,7 @@
 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) {