Fix build with Poppler 0.86 and later.

Taken from Arch Linux, but adjusted to patch the versioned Poppler
files, as upstream applies it after copying them in place.
https://git.archlinux.org/svntogit/packages.git/tree/trunk/texlive-poppler-0.86.patch?h=packages/texlive-bin

--- a/texk/web2c/pdftexdir/pdftoepdf-poppler0.76.0.cc	2020-03-03 21:11:35.102711802 +0000
+++ b/texk/web2c/pdftexdir/pdftoepdf-poppler0.76.0.cc	2020-03-03 21:13:13.057420111 +0000
@@ -757,7 +757,7 @@
     if (page_name) {
         // get page by name
         GString name(page_name);
-        LinkDest *link = pdf_doc->doc->findDest(&name);
+        LinkDest *link = pdf_doc->doc->findDest(&name).get();
         if (link == 0 || !link->isOk())
             pdftex_fail("PDF inclusion: invalid destination <%s>", page_name);
         Ref ref = link->getPageRef();

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<tr><td><span title='2022-05-31 14:54:13 -0400'>2022-05-31</span></td><td><a href='/guix/commit/gnu/packages/openbox.scm?id=f451a8e80cf8d2da08bb65c4c07e3d41d7a17e58'>gnu: openbox: Patch for Python 3.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/patches/openbox-python3.patch: New patch.
* gnu/local.mk (dist_patch_DATA): Register it.
* gnu/packages/openbox.scm (openbox)[source]: Apply it.
[arguments]: New field.
[propagated-inputs]: Replace python2-pyxdg with python-pyxdg.
[native-inputs]: Replace python-2 with python-wrapper.
Add autoconf, automake, gettext-minimal and libtool.
</span></span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2021-12-13 22:15:07 +0100'>2021-12-13</span></td><td><a href='/guix/commit/gnu/packages/openbox.scm?id=e3196755e60ba7f1ed9d432e73f26a85e0c8893c'>gnu: Further simplify package inputs.</a><span class='msg-avail'>...<span class='msg-tooltip'>This is the result of running:

  ./pre-inst-env guix style --input-simplification=safe

and manually undoing changes on a dozen of packages to reduce
rebuilds (derivations for emacs, icecat, and libreoffice are unchanged.)
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-12-13 17:48:25 +0100'>2021-12-13</span></td><td><a href='/guix/commit/gnu/packages/openbox.scm?id=8394619baceb118df92e355377fd543bb1aa501a'>gnu: Simplify package inputs.</a><span class='msg-avail'>...<span class='msg-tooltip'>This commit was obtained by running:

  ./pre-inst-env guix style

without any additional argument.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-12-05 22:42:26 +0100'>2021-12-05</span></td><td><a href='/guix/commit/gnu/packages/openbox.scm?id=c789d00b5f2e71d218107686972d8b99fbc5501f'>gnu: openbox: Use 'librsvg-for-system'.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/openbox.scm (openbox)[inputs]: Use 'librsvg-for-system'
unconditionally.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2021-11-26 23:00:16 +0100'>2021-11-26</span></td><td><a href='/guix/commit/gnu/packages/openbox.scm?id=7668f7c6f3772882aeab80e2fb8ac0d96938433c'>gnu: openbox: Keep librsvg dependency on x86_64 only.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/openbox.scm (openbox)[inputs]: Make LIBRSVG conditional.
</span></span></td><td>Ludovic Courtès</td></tr>