Fix a string comparison in C++ 11.

Taken from Debian:
https://sources.debian.org/src/dbus-c++/0.9.0-8.1/debian/patches/06_fix_gcc-7_ftbfs.patch/

--- a/src/pipe.cpp
+++ b/src/pipe.cpp
@@ -83,5 +83,5 @@ ssize_t Pipe::read(void *buffer, unsigne
 void Pipe::signal()
 {
   // TODO: ignoring return of read/write generates warning; maybe relevant for eventloop work...
-  ::write(_fd_write, '\0', 1);
+  ::write(_fd_write, "\0", 1);
 }
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<tr><td><span title='2022-02-02 16:46:44 +0100'>2022-02-02</span></td><td><a href='/guix/commit/gnu/installer/newt/locale.scm?id=726d0bd2f36363392ba2fcefd6e5d4aeed27dc9e'>installer: Use named prompt to abort or break installer steps.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/installer/steps.scm (run-installer-steps): Set up
'installer-step prompt.
* gnu/installer/newt/ethernet.scm (run-ethernet-page)
* gnu/installer/newt/final.scm (run-config-display-page,
run-install-failed-page)
* gnu/installer/newt/keymap.scm (run-layout-page, run-variant-page)
* gnu/installer/newt/locale.scm (run-language-page,
run-territory-page, run-codeset-page, run-modifier-page,
run-locale-page)
* gnu/installer/newt/network.scm (run-technology-page,
wait-service-online)
* gnu/installer/newt/page.scm (run-listbox-selection-page,
run-checkbox-tree-page)
* gnu/installer/newt/partition.scm (button-exit-action)
* gnu/installer/newt/services.scm (run-desktop-environments-cbt-page,
run-networking-cbt-page, run-other-services-cbt-page,
run-network-management-page)
* gnu/installer/newt/timezone.scm (run-timezone-page)
* gnu/installer/newt/user.scm (run-user-page)
* gnu/installer/newt/welcome.scm (run-menu-page)
* gnu/installer/newt/wifi.scm (run-wifi-page): Use the 'installer-step
prompt to abort.

Signed-off-by: Mathieu Othacehe &lt;othacehe@gnu.org&gt;
</span></span></td><td>Josselin Poiret</td></tr>
<tr><td><span title='2020-09-21 00:31:15 +0200'>2020-09-21</span></td><td><a href='/guix/commit/gnu/installer/newt/locale.scm?id=e1f3788944ee154ba9b33c891c4ccf039a1ff39a'>installer: Fix docstring typoes.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/installer/connman.scm (connman-state, run-locale-page)
(start-swapping, stop-swapping, run-installer-steps): Fix typo in
docstring.
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>