d/rules.d/certs: Add newly required include directory to CPPFLAGS

debian/changelog

@@ -24,6 +24,7 @@ linux (6.12~rc2-1~exp1) UNRELEASED; urgency=medium
       - Adjust context in "intel-iommu: Add option to exclude integrated GPU
         only"
   * [rt] Update to 6.12-rc1-rt2
+  * d/rules.d/certs: Add newly required include directory to CPPFLAGS
  -- Ben Hutchings <benh@debian.org>  Mon, 07 Oct 2024 15:23:24 +0200

debian/rules.d/certs/Makefile

@@ -3,5 +3,5 @@ PROGS = \
 
 include $(top_rulesdir)/Makefile.inc
 
-CPPFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
+CPPFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -I$(top_srcdir)/scripts
 extract-cert: LDLIBS += -lcrypto