uterm: move uterm_input.h to uterm_input_internal.h

We will split the public uterm header soon to avoid big headers. Hence,
rename internal headers to *_internal.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
uterm: move uterm_video.h to uterm_video_internal.h

Same as uterm_input.h, we want internal headers to have the *_internal
suffix.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
uterm: move uterm_systemd.h to uterm_systemd_internal.h

Same as uterm_input.h, we want internal headers to have the *_internal
suffix.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
uterm: monitor: read boot_vga via uterm

Instead of using the pciaccess helpers, we now read the boot_vga flag via
uterm. This makes the whole process a lot simpler and removes a lot of
duplicated code that is already provided by the kernel.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
uterm: video: remove drm_get_id() helper

This helper is no longer used so remove it.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
uterm: remove unused pciaccess helpers

We now detect primary GPUs via udev so the pciaccess helpers are no longer
needed.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
uterm: monitor: avoid libdrm dependency

Instead of depending on libdrm, we simply copy the VERSION-IOCTL ABI and
perform the ioctl ourself. This reduces complexity and dependencies.

Why does the DRM layer not provide normal uapi headers via
linux-api-headers? We should fix that.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>