Rename hb-*private.hh to hb-*.hh

Sorry for the noise, downstream custom builders.  Please adjust.
diff --git a/src/hb-ot-shape-complex-myanmar-machine.rl b/src/hb-ot-shape-complex-myanmar-machine.rl
index 0cd84fa..62f51d1 100644
--- a/src/hb-ot-shape-complex-myanmar-machine.rl
+++ b/src/hb-ot-shape-complex-myanmar-machine.rl
@@ -27,7 +27,7 @@
 #ifndef HB_OT_SHAPE_COMPLEX_MYANMAR_MACHINE_HH
 #define HB_OT_SHAPE_COMPLEX_MYANMAR_MACHINE_HH
 
-#include "hb-private.hh"
+#include "hb.hh"
 
 %%{
   machine myanmar_syllable_machine;