external qrcodegen looks under qrcodegen

Change-Id: I01f06c30a52f5e4cdb5b4b6304072aa0f3a63aa8
Reviewed-on: https://gerrit.libreoffice.org/76291
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

RepositoryExternal.mk

@@ -4160,8 +4160,9 @@ ifneq ($(SYSTEM_QRCODEGEN),)
 
 define gb_LinkTarget__use_qrcodegen
 $(call gb_LinkTarget_set_include,$(1),\
-       $$(INCLUDE) \
-	   $(QRCODEGEN_CFLAGS) \
+	-DSYSTEM_QRCODEGEN \
+	$$(INCLUDE) \
+	$(QRCODEGEN_CFLAGS) \
 )
 $(call gb_LinkTarget_add_libs,$(1),$(QRCODEGEN_LIBS))
 

cui/source/dialogs/QrCodeGenDialog.cxx

@@ -16,7 +16,11 @@
 #include <utility>
 #include <vcl/weld.hxx>
 
+#if defined(SYSTEM_QRCODEGEN)
+#include <qrcodegen/QrCode.hpp>
+#else
 #include <QrCode.hpp>
+#endif
 
 #include <com/sun/star/beans/XPropertySet.hpp>
 #include <com/sun/star/drawing/XDrawPageSupplier.hpp>