Disconnection fixes

Sorry for the mess in the indentation, IAR is weird beast for me.

The main issues addressed here are:

* One timeout was increased from 10ms to 500ms to
give the Gainspan chipset enought time to read incoming
TCP data. The timeout was expiring too soon and
we were explicitly closing the connection due to that.

* The second issue was an unexpected return value returned by
  App_SwarmProducer() which is not an error and was being interpreted as
  an error by our producing source code, closing the connection.

Both were applied in https://github.com/buglabs/bugswarm-renesas/commit/3bc6c6b55d83e11531bef892e88d9b98f13bcfd7