Enable IBM PLDM OEM commands support

Create folder structure (oem/ibm) for ibm pldm oem commands. Move the
files from the ibm-pldm-oem repo [https://github.com/openbmc/ibm-pldm-oem]
to the folder oem/ibm/ under the pldm repo and enable conditional
compilation for it. The test files are also conditionally compiled.

You would need to provide --enable-oem-ibm to configure.

This is done to simplify the build time and runtime dependencies between the
standard and oem implementations.

Signed-off-by: Jinu Joy Thomas <jinu.joy.thomas@in.ibm.com>
Change-Id: Iaa93c73faff87290e3d3d5d155d9ecae6e7ee6f9
diff --git a/libpldmresponder/Makefile.am b/libpldmresponder/Makefile.am
index 1b82777..21cfdc8 100644
--- a/libpldmresponder/Makefile.am
+++ b/libpldmresponder/Makefile.am
@@ -13,9 +13,15 @@
 libpldmresponder_la_CXXFLAGS = \
 	$(CODE_COVERAGE_CXXFLAGS) \
 	$(SDBUSPLUS_CFLAGS)
-
 libpldmresponder_la_CPPFLAGS = \
 	$(CODE_COVERAGE_CPPFLAGS) \
+   	-I$(top_builddir)/libpldm/ \
 	-I$(top_srcdir)
 
+if OEM_IBM
+libpldmresponder_la_SOURCES += \
+    $(top_builddir)/oem/ibm/libpldmresponder/file_io.cpp
+libpldmresponder_la_CPPFLAGS += \
+        -I$(top_builddir)/oem/ibm/
+endif