Revert "Revert "showiframe: no need to write the iframe 7 times""

This reverts commit 748964a7397ef1f8d8be010e9573abdd7c3cf19d.

Reportedly, the same dreamboxes which caused us to re-introduce
the write loop, are now having trouble displaying larger iframes,
because of that write loop.
So let's get rid of the write loop (again).
usbserial: add cp210x usb serial support to et and xp kernels.

Support was already enabled for dmm and vuplus kernels.
dreambox-dvb-modules: update drivers for dm500hd, dm800se and dm7020hd.

This version should enable Dolby Digital Plus aka ac3+ aka DD+.
vuplus solo2: update dvb drivers.

"Fix vtuner problem"
Fix DMM builds after recent changes in dvb audio sink.

When downmix is enabled we remove on runtime the dts caps to give priority on dtsdownmix.

Also provide a simple way to check if ac3plus is enabled using cheap access call

Signed-off-by: Erik Slagter <erik@slagter.name>
showiframe: use blocking writes
vuplus-dvb-modules-vusolo2: correct wrong checksums from commit
3dd81e58f90baa776ff3df59090e46f711500d7c.
Add a proper fix for DTS Passthrough

Using my previous patch we were getting the following error

(gst-launch-0.10:811): GStreamer-CRITICAL **: gst_caps_remove_structure: assertion `IS_WRITABLE (caps)' failed
(gst-launch-0.10:811): GStreamer-CRITICAL **: gst_caps_remove_structure: assertion `IS_WRITABLE (caps)' failed

Because we forget to make caps writable.

> -             caps = gst_static_caps_get(&hwtemplate->static_caps);
> +             caps = gst_caps_copy(&hwtemplate->static_caps.caps);

Signed-off-by: pieterg <pieterg@users.sourceforge.net>
Merge branch 'master' of git://git.code.sf.net/p/openpli/openpli-oe-core