move headers to include/osmocom/hlr

Apply the same headers structure that we keep in most Osmocom source trees:
Keep noinst_HEADERS in include/osmocom/hlr and include them using
  #include <osmocom/hlr/*.h>

The only header kept in src/ is db_bootstrap.h, because it is generated during
build time. If it was built in include/osmocom/hlr, we would need db.o to
depend on db_bootstrap.h in a different subdir, which automake can't do well.

Change-Id: Ic912fe27f545b85443c5fb713d8c3c8aac23c9ad
diff --git a/tests/gsup_server/Makefile.am b/tests/gsup_server/Makefile.am
index 686ce37..e64ac4a 100644
--- a/tests/gsup_server/Makefile.am
+++ b/tests/gsup_server/Makefile.am
@@ -1,11 +1,11 @@
 AM_CPPFLAGS = \
 	$(all_includes) \
-	-I$(top_srcdir)/src \
 	$(NULL)
 
 AM_CFLAGS = \
 	-Wall \
 	-ggdb3 \
+	-I$(top_srcdir)/include \
 	$(LIBOSMOCORE_CFLAGS) \
 	$(LIBOSMOGSM_CFLAGS) \
 	$(LIBOSMOABIS_CFLAGS) \