[zk-token-sdk] Check that discrete log compression batch size is grea…

…ter than 0 (solana-labs#33699)

check that discrete log compression batch size is greater than 0

zk-token-sdk/src/encryption/discrete_log.rs

@@ -130,7 +130,7 @@ impl DiscreteLog {
         &mut self,
         compression_batch_size: usize,
     ) -> Result<(), DiscreteLogError> {
-        if compression_batch_size >= TWO16 as usize {
+        if compression_batch_size >= TWO16 as usize || compression_batch_size == 0 {
             return Err(DiscreteLogError::DiscreteLogBatchSize);
         }
         self.compression_batch_size = compression_batch_size;