Implement response encode/request decode for ReadFileIntoMemory

The ReadFileIntoMemory command is an OEM command to support large
size transfer from BMC to Host via DMA mechanism.

Change-Id: I416a1af8a4d1ea91a7dffbbb98ae58eeccf6d0ea
Signed-off-by: Tom Joseph <tomjoseph@in.ibm.com>
8 files changed