Fix typo on CEA-708 decoder

Issue: #2595

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=151004198

library/core/src/main/java/com/google/android/exoplayer2/text/cea/Cea708Decoder.java

@@ -483,7 +483,7 @@ public final class Cea708Decoder extends CeaDecoder {
 
   private void handleC2Command(int command) {
     // C2 Table doesn't contain any commands in CEA-708-B, but we do need to skip bytes
-    if (command <= 0x0F) {
+    if (command <= 0x07) {
       // Do nothing.
     } else if (command <= 0x0F) {
       serviceBlockPacket.skipBits(8);