Avoid a type mismatch that shows up in C++11.
Taken from <https://bugs.debian.org/853560>.

--- a/src/rtphint.cpp	2012-05-20 16:11:53.000000000 -0600
+++ b/src/rtphint.cpp	2017-05-16 10:25:26.930705191 -0600
@@ -339,7 +339,7 @@
                 pSlash = strchr(pSlash, '/');
                 if (pSlash != NULL) {
                     pSlash++;
-                    if (pSlash != '\0') {
+                    if (*pSlash != '\0') {
                         length = (uint32_t)strlen(pRtpMap) - (pSlash - pRtpMap);
                         *ppEncodingParams = (char *)MP4Calloc(length + 1);
                         strncpy(*ppEncodingParams, pSlash, length);
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<tr><td><span title='2022-05-26 11:41:05 +0200'>2022-05-26</span></td><td><a href='/guix/commit/build-aux/cuirass/evaluate.scm?id=d90bd5642a3663cc7d5124068fadbf8fa28b3207'>cuirass: Create just as many threads as needed.</a><span class='msg-avail'>...<span class='msg-tooltip'>* build-aux/cuirass/evaluate.scm (command-line): Change second argument
to 'n-par-for-each'.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-05-26 11:41:05 +0200'>2022-05-26</span></td><td><a href='/guix/commit/build-aux/cuirass/evaluate.scm?id=98a6642298be6663b9d318b7dea46d1dba275839'>cuirass: Fork inferior processes before creating threads.</a><span class='msg-avail'>...<span class='msg-tooltip'>Works around &lt;https://issues.guix.gnu.org/55441#12&gt;.

Start from commit bd86bbd300474204878e927f6cd3f0defa1662a5,
'open-inferior' uses 'primitive-fork' instead of 'open-pipe*'.  As a
result, child process could potentially hang before calling 'execl' due
to undefined behavior when forking a multi-threaded process.

* build-aux/cuirass/evaluate.scm &lt;top level&gt;: Call 'open-inferior'
before 'n-par-for-each'.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2022-05-20 18:46:07 +0200'>2022-05-20</span></td><td><a href='/guix/commit/build-aux/cuirass/evaluate.scm?id=598f7289db9955584457ffc11c8504f3938a1618'>cuirass: Close each inferior upon completion.</a><span class='msg-avail'>...<span class='msg-tooltip'>* build-aux/cuirass/evaluate.scm &lt;top level&gt;: Add 'close-inferior' call.
</span></span></td><td>Ludovic Courtès</td></tr>