if we can't read anymore, return..

[git-p4: depot-paths = "//depot/": change = 919]

mpegts/mpegts.py

@@ -1201,7 +1201,10 @@ class TSPStream:
 						buf = buf[start + 1:]
 						continue
 				except IndexError:
-					buf += self.f.read(READBLK)
+					nbuf = self.f.read(READBLK)
+					if not nbuf:
+						return
+					buf += nbuf
 
 				continue