rtmp: Unbreak handle_notify

Commit 5626f994 broke it.

libavformat/rtmpproto.c

@@ -2067,7 +2067,7 @@ static int handle_notify(URLContext *s, RTMPPacket *pkt) {
     GetByteContext gbc;
     PutByteContext pbc;
     uint32_t ts;
-    int old_flv_size;
+    int old_flv_size, err;
     const uint8_t *datatowrite;
     unsigned datatowritelength;
 
@@ -2095,10 +2095,11 @@ static int handle_notify(URLContext *s, RTMPPacket *pkt) {
         old_flv_size  = rt->flv_size;
         rt->flv_size += datatowritelength + 15;
     } else {
-        int err;
         old_flv_size = 0;
         rt->flv_size = datatowritelength + 15;
         rt->flv_off  = 0;
+    }
+
     if ((err = av_reallocp(&rt->flv_data, rt->flv_size)) < 0)
         return err;
     bytestream2_init_writer(&pbc, rt->flv_data, rt->flv_size);
@@ -2110,7 +2111,7 @@ static int handle_notify(URLContext *s, RTMPPacket *pkt) {
     bytestream2_put_be24(&pbc, 0);
     bytestream2_put_buffer(&pbc, datatowrite, datatowritelength);
     bytestream2_put_be32(&pbc, 0);
-    }
+
     return 0;
 }