client API: remove SIGPIPE overriding code

This workaround prevented that libmpv users could accidentally crash
when the SIGPIPE signal was triggered by FFmpeg's OpenSSL/GnuTLS usage.
But it also modifies the global signal handler state, so remove it now
that this workaround is not required anymore.

input/ipc-unix.c

@@ -20,6 +20,7 @@
 #include <unistd.h>
 
 #include <poll.h>
+#include <signal.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <sys/stat.h>
@@ -97,6 +98,11 @@ static void *client_thread(void *p)
 {
     pthread_detach(pthread_self());
 
+    // We don't use MSG_NOSIGNAL because the moldy fruit OS doesn't support it.
+    struct sigaction sa = { .sa_handler = SIG_IGN, .sa_flags = SA_RESTART };
+    sigfillset(&sa.sa_mask);
+    sigaction(SIGPIPE, &sa, NULL);
+
     int rc;
 
     struct client_arg *arg = p;