build: autotools files for libopenpower_dbus.so

Use the interface YAML files present to generate the server.cpp
and server.hpp files, build them into a shared library, and
install.

Change-Id: I87217ba299c04b3eb3fac819463707a103a287b5
Signed-off-by: Deepak Kodihalli <dkodihal@in.ibm.com>
diff --git a/Makefile.interfaces.in b/Makefile.interfaces.in
new file mode 100644
index 0000000..714e6d0
--- /dev/null
+++ b/Makefile.interfaces.in
@@ -0,0 +1 @@
+# Empty file so that 'configure' attempts to generate Makefile.interfaces.