ivi-shell: install ivi-layout-export.h

IVI-Shell is designed to be used with other controller modules
than hmi-controller.These controller modules require
the ivi-layout-export header file to properly integrate
with the ivi-shell. The header file should be installed
when ivi-shell is enabled, because these controller modules
are not a part of the weston repository.

Signed-off-by: Emre Ucan <eucan@de.adit-jv.com>
Reviewed-by: Bryce Harrington <bryce@osg.samsung.com>
diff --git a/Makefile.am b/Makefile.am
index 1900390..13c43bf 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -215,6 +215,11 @@
 	shared/zalloc.h				\
 	shared/platform.h
 
+if ENABLE_IVI_SHELL
+westoninclude_HEADERS +=				\
+	ivi-shell/ivi-layout-export.h
+endif
+
 if ENABLE_EGL
 module_LTLIBRARIES += gl-renderer.la
 gl_renderer_la_LDFLAGS = -module -avoid-version