Fix Perl module Module::Pluggable such that it can find plugins that live in
symlinked directories.

Patch borrowed/adapted from Nixpkgs.

--- Module-Pluggable-5.2/lib/Module/Pluggable/Object.pm   2015-04-08 23:28:48.120164135 -0500
+++ Module-Pluggable-5.2/lib/Module/Pluggable/Object.pm   2015-04-08 23:30:27.032166704 -0500
@@ -164,7 +164,7 @@
         my $sp = catdir($dir, (split /::/, $searchpath));

         # if it doesn't exist or it's not a dir then skip it
-        next unless ( -e $sp && -d _ ); # Use the cached stat the second time
+        next unless ( -e $sp );

         my @files = $self->find_files($sp);

@@ -279,7 +279,7 @@
                              (my $path = $File::Find::name) =~ s#^\\./##;
                              push @files, $path;
                            }
-                      }, $search_path );
+                      }, "$search_path/." );
     }
     #chdir $cwd;
     return @files;</td><td class='sub right'></td></tr></table>
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<tr><td><span title='2018-06-17 21:29:07 +0530'>2018-06-17</span></td><td><a href='/guix/commit/gnu/packages/tex.scm?id=b4eae997fe5b928f179c34d281e9f2c3eccd3670'>gnu: texlive-bin: Use absolute path to ghostscript executable "gs".</a><span class='msg-avail'>...</span></td><td>Arun Isaac</td></tr>