Description of problem:
Package graphviz fails to build from source in Fedora Rawhide with SWIG 4.1.0.

libtool: warning: remember to run 'libtool --finish /usr/lib64/graphviz/perl'
 /usr/bin/mkdir -p '/builddir/build/BUILDROOT/graphviz-7.0.0-1.fc38.x86_64/usr/lib64/graphviz/php'
 /usr/bin/install -p -m 644 ./gv.php '/builddir/build/BUILDROOT/graphviz-7.0.0-1.fc38.x86_64/usr/lib64/graphviz/php'
/usr/bin/install: cannot stat './gv.php': No such file or directory
make[5]: *** [Makefile:2711: install-pkgphpDATA] Error 1

The source of the failure is this change:
2021-05-04: olly
   [PHP] #1982 #1457 https://sourceforge.net/p/swig/bugs/1339/
   SWIG now only use PHP's C API to implement its wrappers, and no
   longer generates PHP code to define classes.  The wrappers should
   be almost entirely compatible with those generated before, but
   faster and without some previously hard-to-fix bugs.

   The main notable difference is SWIG no longer generates a .php
   wrapper at all by default (only if %pragma(php) code=... or
   %pragma(php) include=... are specified in the interface file).
   This also means you need to load the module via extension=...
   in php.ini, rather than letting the dl() in the generated
   .php wrapper load it (but dl() has only worked for command-line
   PHP for some years now).

   *** POTENTIAL INCOMPATIBILITY ***

The error was reported to the upstream.

Additional info:
This package is tracked by Koschei. See:
https://koschei.fedoraproject.org/package/graphviz