parasite: Initialize fd in parasite_get_proc_fd

Otherwise I get

 | parasite.c: In function ‘parasite_service’:
 | parasite.c:383:11: error: ‘fd’ may be used uninitialized in this function [-Werror=uninitialized]
 | cc1: all warnings being treated as errors
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

parasite.c

@@ -380,7 +380,7 @@ static int init(struct parasite_init_args *args)
 static char proc_mountpoint[] = "proc.crtools";
 static int parasite_get_proc_fd()
 {
-	int ret, fd;
+	int ret, fd = -1;
 	char buf[2];
 
 	ret = sys_readlink("/proc/self", buf, sizeof(buf));