travis: add Gallium state-tracker targets

Split into OpenCL and others, since the former is quite time consuming.

v2:
 - explicitly enable/disable components
 - build libvdpau 1.1 requirement
 - enable st/vdpau
 - build libva 1.6.2 (API 0.38) requirement

v3: Drop ubuntu-toolchain-r-test from sources (Andres)

Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Andres Gomez <agomez@igalia.com>
1 file changed