contrib: gpg-error: use CPPFLAGS when processing errno.h

contrib/src/gpg-error/cppflags.patch

+--- libgpg-error/src/Makefile.am.orig	2012-06-20 11:39:51.650987881 +0200
++++ libgpg-error/src/Makefile.am	2012-06-20 11:40:09.266987882 +0200
+@@ -138,7 +138,7 @@
+ # It is correct to use $(CPP).  We want the host's idea of the error codes.
+ mkerrcodes.h: Makefile mkerrcodes.awk $(gpg_extra_headers)
+ 	$(AWK) -f $(srcdir)/mkerrcodes1.awk $(srcdir)/errnos.in >_$@
+-	$(CPP) $(extra_cppflags) _$@ | grep GPG_ERR_ | \
++	$(CPP) $(CPPFLAGS) $(extra_cppflags) _$@ | grep GPG_ERR_ | \
+                $(AWK) -f $(srcdir)/mkerrcodes.awk >$@
+ 	-rm _$@
+ 

contrib/src/gpg-error/rules.mak

@@ -12,9 +12,11 @@ libgpg-error: libgpg-error-$(GPGERROR_VERSION).tar.bz2 .sum-gpg-error
 ifdef HAVE_WIN32
 	$(APPLY) $(SRC)/gpg-error/windres-make.patch
 endif
+	$(APPLY) $(SRC)/gpg-error/cppflags.patch
 	$(MOVE)
 
 .gpg-error: libgpg-error
+	$(RECONF)
 	cd $< && $(HOSTVARS) ./configure $(HOSTCONF) --disable-nls --disable-shared --disable-languages
 	cd $< && $(MAKE) install
 	touch $@