journal-remote-main: pass the right error variable

(cherry picked from commit 47eab95)
(cherry picked from commit 8871097)

src/journal-remote/journal-remote-main.c

@@ -108,7 +108,7 @@ static int spawn_child(const char* child, char** argv) {
 
         r = fd_nonblock(fd[0], true);
         if (r < 0)
-                log_warning_errno(errno, "Failed to set child pipe to non-blocking: %m");
+                log_warning_errno(r, "Failed to set child pipe to non-blocking: %m");
 
         return fd[0];
 }