Include sockLib header to enable usage of socket functions on VxWorks

Functions normally found from <sys/socket.h> are available on VxWorks
from <sockLib.h> header.

Change-Id: I2263ec40ba9f37bc95755b633fb43d66ceb2777c
Reviewed-by: Samuel Rødal <samuel.rodal@digia.com>
Find primary GPU only

Some systems may have multiple DRM devices attached to a single seat and we are
not guaranteed to pick up the primary GPU. With this flag we can control how
DRM devices are detected and consider only the primary GPU.

This is very useful for the kms plugin or QtCompositors running on kms in order
to use the right DRM device.

Change-Id: I8b91e78f148b25aaa4e40724e39e0ed0918ca100
Reviewed-by: Andy Nichols <andy.nichols@digia.com>
Made EGLFS handle multiple surfaces with more grace.

Prevents crashing when some menu or similar is shown, although the
visual result might not be ideal.

Task-number: QTBUG-29729
Change-Id: Ia840b3ec17f5ef30ee58150bd2f807ca5e72cc12
Reviewed-by: Gunnar Sletta <gunnar.sletta@digia.com>
Reviewed-by: Andy Nichols <andy.nichols@digia.com>
Added automatic input device discovery to kms plugin.

Similar to what the EGLFS plugin does, to avoid having to explicitly
specify which device to use for keyboard and mouse.

Change-Id: I00502be8c767487490f3fd36fb06d3eb56548ada
Reviewed-by: Pier Luigi Fiorini <pierluigi.fiorini@gmail.com>
Reviewed-by: Andy Nichols <andy.nichols@digia.com>