libv4l-rockchip_v2: Add more ioctls to v4l_cmd2str()

Add a couple more ioctls used by Chromium's V4L2 VEA so that the plugin
debug messages don't show "UNKNOWN" ioctl.

BUG=b:206718749
TEST=Run vea_tests with LIBV4L_PLUGIN_LOG_LEVEL=4

Change-Id: Ia81fe160a2024986330ad177aa83171e601f2f49
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/libv4lplugins/+/3308615
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Reviewed-by: Tomasz Figa <tfiga@chromium.org>
Commit-Queue: Chen-Yu Tsai <wenst@chromium.org>