Fix CombineBlocks optimization

(df_attributes & DF_DA) means Get not Put.
The patch fixes the condition to eliminate catch block for
get/put operations.

Change-Id: I48036f3614de5116e27c0d6e9a7a342432c9a828
Signed-off-by: Serguei Katkov <serguei.i.katkov@intel.com>