Improve block1 streaming
Improve block1 streaming

Update the le_coap_SendResponse function and the CoAP
message handler:
Add the block size in order to manage the block size
negociation

Resolves: LE-13900
Change-Id: I296b255fc5b48e57d9b16eb9e984d7c61f57d205

legatoproject/legato-af,legatoproject/legato-af,legatoproject/legato-af,legatoproject/legato-af,legatoproject/legato-af,legatoproject/legato-af,legatoproject/legato-af,legatoproject/legato-af,legatoproject/legato-af