Remove osmo-iuh subdir level from include/ (2/2)

Make all changes to #include statements and build files.
diff --git a/include/osmocom/hnbap/IE-Extensions.h b/include/osmocom/hnbap/IE-Extensions.h
index d56c93e..5236df0 100644
--- a/include/osmocom/hnbap/IE-Extensions.h
+++ b/include/osmocom/hnbap/IE-Extensions.h
@@ -38,7 +38,7 @@
 #endif
 
 /* Referred external types */
-#include <osmocom/osmo-iuh/hnbap/IE.h>
+#include <osmocom/hnbap/IE.h>
 
 #endif	/* _IE_Extensions_H_ */
 #include <asn_internal.h>