Minimally patch libtheora's ancient config.guess to support mips64.

--- libtheora/config.guess.orig	2009-02-23 22:50:50.000000000 -0500
+++ libtheora/config.guess	2013-10-31 23:49:48.155999944 -0400
@@ -798,25 +798,24 @@
     m68*:Linux:*:*)
 	echo ${UNAME_MACHINE}-unknown-linux-gnu
 	exit 0 ;;
-    mips:Linux:*:*)
+    mips:Linux:*:* | mips64:Linux:*:*)
 	eval $set_cc_for_build
 	sed 's/^	//' << EOF >$dummy.c
 	#undef CPU
-	#undef mips
-	#undef mipsel
+	#undef ${UNAME_MACHINE}
+	#undef ${UNAME_MACHINE}el
 	#if defined(__MIPSEL__) || defined(__MIPSEL) || defined(_MIPSEL) || defined(MIPSEL)
-	CPU=mipsel
+	CPU=${UNAME_MACHINE}el
 	#else
 	#if defined(__MIPSEB__) || defined(__MIPSEB) || defined(_MIPSEB) || defined(MIPSEB)
-	CPU=mips
+	CPU=${UNAME_MACHINE}
 	#else
 	CPU=
 	#endif
 	#endif
 EOF
-	eval `$CC_FOR_BUILD -E $dummy.c 2>/dev/null | grep ^CPU=`
-	rm -f $dummy.c && rmdir $tmpdir
-	test x"${CPU}" != x && echo "${CPU}-pc-linux-gnu" && exit 0
+	eval `$CC_FOR_BUILD -E $dummy.c 2>/dev/null | grep '^CPU'`
+	test x"${CPU}" != x && { echo "${CPU}-unknown-linux-gnu"; exit 0; }
 	;;
     ppc:Linux:*:*)
 	echo powerpc-unknown-linux-gnu
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<div class='path'>path: <a href='/guix/log/?id=e2dae72dabae761ea154855fae14def77b41b76c'>root</a>/<a href='/guix/log/doc?id=e2dae72dabae761ea154855fae14def77b41b76c'>doc</a>/<a href='/guix/log/doc/guix-cookbook.texi?id=e2dae72dabae761ea154855fae14def77b41b76c'>guix-cookbook.texi</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/doc/guix-cookbook.texi?id=e2dae72dabae761ea154855fae14def77b41b76c&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2021-07-07 11:13:38 +0200'>2021-07-07</span></td><td><a href='/guix/commit/doc/guix-cookbook.texi?id=c2ff06e5e410e615397b9df901af8028a64b3d82'>doc: Add guide showing auto-login on a specific TTY to the cookbook.</a><span class='msg-avail'>...<span class='msg-tooltip'>This is a follow-up to the discussion in &lt;https://bugs.gnu.org/48974&gt;.

* doc/guix-cookbook.texi (System Configuration): Add a brief guide that
explains auto login a user to one TTY.

* doc/guix.texi (System Services): Add an texinfo anchor, so that the cookbook
entry "Auto Login a User to a Specific TTY" can refer back to the precise
point that the GNU Guix Reference manual.  Also add a reference to the
cookbook that shows how to auto login a specific user to one TTY.

Signed-off-by: Leo Prikler &lt;leo.prikler@student.tugraz.at&gt;
</span></span></td><td>Joshua Branson</td></tr>
<tr><td><span title='2021-01-21 14:40:36 +0100'>2021-01-21</span></td><td><a href='/guix/commit/doc/guix-cookbook.texi?id=07ef129db31d9738668100681babd8547f071f6e'>doc: cookbook: Add "Guix System Image API" section.</a><span class='msg-avail'>...<span class='msg-tooltip'>* doc/guix-cookbook.texi (Guix System Image API): New section.

Signed-off-by: Mathieu Othacehe &lt;othacehe@gnu.org&gt;
</span></span></td><td>Joshua Branson</td></tr>
<tr><td><span title='2021-01-20 16:16:45 +0100'>2021-01-20</span></td><td><a href='/guix/commit/doc/guix-cookbook.texi?id=2a9784ffa247bb2580346b7ce1d3f23c302459a3'>doc: Replace TP with Weblate mentions.</a><span class='msg-avail'>...<span class='msg-tooltip'>* doc/contributing.texi: Replace link to TP with a link to Weblate.
* doc/guix.texi: Replace link to TP with a link to Weblate.
* doc/guix-cookbook.texi: Replace link to TP with a link to Weblate.
</span></span></td><td>Julien Lepiller</td></tr>
<tr><td><span title='2020-12-23 11:45:06 +0100'>2020-12-23</span></td><td><a href='/guix/commit/doc/guix-cookbook.texi?id=af67e8d0b12d164d521c0910a6ae8a8e7d941099'>doc: cookbook: Fix "fiction-less" typo.</a><span class='msg-avail'>...<span class='msg-tooltip'>* doc/guix-cookbook.texi (Guix Profiles in Practice): Change "friction-less"
to "frictionless".
</span></span></td><td>Pierre Neidhardt</td></tr>