ffdc: Convert telnet return data to ASCII string.

telnetlib return data as a binary list.
Convert return data to ASCII string for processing.

Test:
- Regression test to telnet servers.

Signed-off-by: Peter D  Phan <peterp@us.ibm.com>
Change-Id: I3ed066556a026370ea2e4a641d64bea90f9c5124
diff --git a/ffdc/ffdc_collector.py b/ffdc/ffdc_collector.py
index ceb0c67..1711c71 100644
--- a/ffdc/ffdc_collector.py
+++ b/ffdc/ffdc_collector.py
@@ -389,7 +389,7 @@
                                        + self.ffdc_prefix
                                        + targ_file)
                 # Creates a new file
-                with open(targ_file_with_path, 'wb') as fp:
+                with open(targ_file_with_path, 'w') as fp:
                     fp.write(result)
                     fp.close
                     telnet_files_saved.append(targ_file)
diff --git a/ffdc/lib/telnet_utility.py b/ffdc/lib/telnet_utility.py
index e2a3adf..4ffa98f 100644
--- a/ffdc/lib/telnet_utility.py
+++ b/ffdc/lib/telnet_utility.py
@@ -125,5 +125,5 @@
 
             logging.error("\t\t ERROR %s " % msg)
 
-        # Return binary data.
-        return local_buffer
+        # Return ASCII string data with ending PROMPT stripped
+        return local_buffer.decode('ascii', 'ignore').replace('$ ', '\n')