Minor adjustments

Got read of endOfData variable in favor of check based on bytesLeft

Author: ArtsemKurantsou

libraries/exoplayer_rtsp/src/main/java/androidx/media3/exoplayer/rtsp/reader/RtpH265Reader.java

@@ -203,12 +203,11 @@ private void processAggregationPacket(ParsableByteArray data)
 
     // Since sprop-max-don-diff != 0 is not supported, DONL won't present in the packet.
 
-    int endOfData = data.bytesLeft();
     data.setPosition(2); // skipping payload header (2 bytes)
     do {
       short nalUnitSize = data.readShort(); // 2 bytes of NAL unit size
       int nalHeaderType = (data.getData()[data.getPosition()] >> 1) & 0x3F;
-      if (data.getPosition() + nalUnitSize > endOfData) {
+      if (data.bytesLeft() < nalUnitSize) {
         throw ParserException.createForMalformedManifest(
             "Malformed Aggregation Packet. NAL unit size exceeds packet size.",
             /* cause= */ null