haiku: Add missing HGL include directory

Author: kallisti5

src/hgl/libgl-haiku/Makefile

@@ -15,6 +15,7 @@ OBJECTS = $(SOURCES:.cpp=.o)
 INCLUDES = -I. \
     -I$(TOP)/include \
     -I$(TOP)/include/GL/internal \
+    -I$(TOP)/include/HGL \
     -I$(TOP)/src/mesa \
 	-I$(TOP)/src/mesa/main \
     -I$(TOP)/src/mapi \

src/mesa/drivers/haiku/swrast/Makefile

@@ -23,6 +23,7 @@ INCLUDES = \
 	-I. \
 	-I- \
 	-I$(TOP)/include \
+	-I$(TOP)/include/HGL \
 	-I/boot/system/develop/headers/private/interface/
 
 DRIVER_SOURCES = \