dump: Add close fd on error return to avoid resource leak

Reported-by: Coverity CID 1523842 (RESOURCE_LEAK)
Fixes: e654919 ("dump: Add command interface for kdump-raw formats")
Signed-off-by: Zongmin Zhou <zhouzongmin@kylinos.cn>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20231107024417.585475-1-min_halo@163.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>

dump/dump.c

@@ -2160,6 +2160,7 @@ void qmp_dump_guest_memory(bool paging, const char *protocol,
         return;
     }
     if (kdump_raw && lseek(fd, 0, SEEK_CUR) == (off_t) -1) {
+        close(fd);
         error_setg(errp, "kdump-raw formats require a seekable file");
         return;
     }