In -current, chromium (and derivatives) gain VA-API support

Following the previous reverted attempt[see earlier report],Robert Nagy (robert@)committed VA-API[hardware-assisted video- see previous report]support to thechromiumandungoogled-chromiumports.The iridiumport can be expected to follow on next update.

Note that:

• Updated (binary) packages are not yet available at the time of writing.
• Intel GPUs requires ports graphics/intel-media-driver [and/]or graphics/intel-vaapi-driver.