make-dist: patch rapidjson to fix FTBFS on GCC 14

Without this, the build fails on GCC 14:

[ 3456s] /home/abuild/rpmbuild/BUILD/ceph-16.2.15-68-gbb20a17289a/src/rapidjson/include/rapidjson/document.h: In member function ‘rapidjson::GenericStringRef<CharType>& rapidjson::GenericStringRef<CharType>::operator=(const rapidjson::GenericStringRef<CharType>&)’:
[ 3456s] /home/abuild/rpmbuild/BUILD/ceph-16.2.15-68-gbb20a17289a/src/rapidjson/include/rapidjson/document.h:319:82: error: assignment of read-only member ‘rapidjson::GenericStringRef<CharType>::length’
[ 3456s]   319 |     GenericStringRef& operator=(const GenericStringRef& rhs) { s = rhs.s; length = rhs.length; }
[ 3456s]       |                                                                           ~~~~~~~^~~~~~~~~~~~
[ 3456s] make[2]: *** [src/rgw/CMakeFiles/rgw_common.dir/build.make:1774: src/rgw/CMakeFiles/rgw_common.dir/rgw_crypt.cc.o] Error 1
[ 3456s] make[1]: *** [CMakeFiles/Makefile2:8011: src/rgw/CMakeFiles/rgw_common.dir/all] Error 2

The copy assignment operator was disabled in upstream rapidjson a very,
very, very long time ago:

Tencent/rapidjson@862c39b

This method of patching a submodule is pretty heinous, even for me.
The alternative would be to fork ceph's (very) old rapidjson to the
SUSE org, apply this path to that fork, and update ceph's .gitmodules
file to point to that instead of the ceph one.

Signed-off-by: Tim Serong <[email protected]>

make-dist

@@ -219,6 +219,29 @@ for tarball in $outfile.version   \
     rm $tarball.tar
 done
 mv $outfile.all.tar $outfile.tar
+patch -p0 <<EOF
+--- src/rapidjson/include/rapidjson/document.h.orig	2024-04-09 16:01:06.252689115 +1000
++++ src/rapidjson/include/rapidjson/document.h	2024-04-09 16:01:29.129152799 +1000
+@@ -316,8 +316,6 @@
+ 
+     GenericStringRef(const GenericStringRef& rhs) : s(rhs.s), length(rhs.length) {}
+ 
+-    GenericStringRef& operator=(const GenericStringRef& rhs) { s = rhs.s; length = rhs.length; }
+-
+     //! implicit conversion to plain CharType pointer
+     operator const Ch *() const { return s; }
+ 
+@@ -328,6 +326,8 @@
+     //! Disallow construction from non-const array
+     template<SizeType N>
+     GenericStringRef(CharType (&str)[N]) /* = delete */;
++    //! Copy assignment operator not permitted - immutable type
++    GenericStringRef& operator=(const GenericStringRef& rhs) /* = delete */;
+ };
+ 
+ //! Mark a character pointer as constant string
+EOF
+tar --update -f $outfile.tar $outfile/src/rapidjson/include/rapidjson/document.h
 rm $outfile
 
 echo "compressing..."