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>
diff --git a/.gitignore b/.gitignore
index 6148c38..ba334df 100644
--- a/.gitignore
+++ b/.gitignore
@@ -60,3 +60,4 @@
 /test-suite.log
 /test/*.gcda
 /test/*.gcno
+/test/libpldm_fileio_test