Workaround for PATH_MAX usage on the Hurd.

Taken from https://salsa.debian.org/debian/screen/-/blob/master/debian/patches/61-default-PATH_MAX-if-undefined-for-hurd.patch

Description: Set PATH_MAX to 4096 if undefined
 Fixes FTBFS since 4.4.0 on GNU/Hurd. Updated to add one more occurrence for 4.5.0.
Author: Axel Beckert <abe@debian.org>
Bug: https://savannah.gnu.org/bugs/?50089
Last-Updated: 2017-01-18

--- a/tty.sh
+++ b/tty.sh
@@ -1478,6 +1478,13 @@
   return 0;
 }
 
+/*
+ * Define PATH_MAX to 4096 if it's not defined, like on GNU/Hurd
+ */
+
+#ifndef PATH_MAX
+#define PATH_MAX 4096
+#endif
 
 int CheckTtyname (char *tty)
 {
--- a/screen.h
+++ b/screen.h
@@ -109,6 +109,13 @@
 # define DEFAULT_BUFFERFILE	"/tmp/screen-exchange"
 #endif
 
+/*
+ * Define PATH_MAX to 4096 if it's not defined, like on GNU/Hurd
+ */
+
+#ifndef PATH_MAX
+#define PATH_MAX 4096
+#endif
 
 #if defined(hpux) && !(defined(VSUSP) && defined(VDSUSP) && defined(VWERASE) && defined(VLNEXT))
 # define HPUX_LTCHARS_HACK
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<tr><td><span title='2023-02-19 01:00:15 +0100'>2023-02-19</span></td><td><a href='/guix/commit/gnu/packages/nano.scm?id=53a739ae5d05c3278f09e05f0cba13d698031d92'>gnu: nano: Update to 7.2.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/nano.scm (nano): Update to 7.2.

Signed-off-by: Tobias Geerinckx-Rice &lt;me@tobias.gr&gt;
</span></span></td><td>Vasile Dumitrascu via Guix-patches via</td></tr>
<tr><td><span title='2022-12-11 01:00:00 +0100'>2022-12-11</span></td><td><a href='/guix/commit/gnu/packages/nano.scm?id=dbbca61bf0a83ac9cbb1cea12f11cb0ee3c28f2f'>gnu: nano: Update to 7.1.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/nano.scm (nano): Update to 7.1.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2022-11-13 01:00:06 +0100'>2022-11-13</span></td><td><a href='/guix/commit/gnu/packages/nano.scm?id=d2b4226709d2ba6e59a385613eef5c0537c2ff4b'>gnu: nano: Update to 7.0.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/nano.scm (nano): Update to 7.0.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2022-08-02 19:09:22 +0300'>2022-08-02</span></td><td><a href='/guix/commit/gnu/packages/nano.scm?id=e1fb703e3ecebcbd0b81177e55ad917e7a5ceb19'>gnu: nano: Update to 6.4.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/nano.scm (nano): Update to 6.4.
</span></span></td><td>Efraim Flashner</td></tr>
<tr><td><span title='2022-05-25 15:41:31 +0300'>2022-05-25</span></td><td><a href='/guix/commit/gnu/packages/nano.scm?id=e0e1bf440937b3f68d29839fb7c5d70061a3129d'>gnu: nano: Update to 6.3.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages/nano.scm (nano): Update to 6.3.
</span></span></td><td>Efraim Flashner</td></tr>