sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

Revert drm2 removal.

Revert r338177, r338176, r338175, r338174, r338172

After long consultations with re@, core members and mmacy, revert
these changes. Followup changes will be made to mark them as
deprecated and prent a message about where to find the up-to-date
driver. Followup commits will be made to make this clear in the
installer. Followup commits to reduce POLA in ways we're still
exploring.

It's anticipated that after the freeze, this will be removed in
13-current (with the residual of the drm2 code copied to
sys/arm/dev/drm2 for the TEGRA port's use w/o the intel or
radeon drivers).

Due to the impending freeze, there was no formal core vote for
this. I've been talking to different core members all day, as well as
Matt Macey and Glen Barber. Nobody is completely happy, all are
grudgingly going along with this. Work is in progress to mitigate
the negative effects as much as possible.

Requested by: re@ (gjb, rgrimes)

Remove legacy drm and drm2 from tree

As discussed on the MLs drm2 conflicts with the ports' version and there
is no upstream for most if not all of drm. Both have been merged in to
a single port.

Users on powerpc, 32-bit hardware, or with GPUs predating Radeon
and i915 will need to install the graphics/drm-legacy-kmod. All
other users should be able to use one of the LinuxKPI-based ports:
graphics/drm-stable-kmod, graphics/drm-next-kmod, graphics/drm-devel-kmod.

MFC: never
Approved by: core@

drm/i915: Update to match Linux 3.8.13

This update brings initial support for Haswell GPUs.

Tested by: Many users of FreeBSD, PC-BSD and HardenedBSD
Relnotes: yes
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D5554

drm: Update the device-independent code to match Linux 3.8.13

This update brings few features:
o Support for the setmaster/dropmaster ioctls. For instance, they
are used to run multiple X servers simultaneously.
o Support for minor devices. The only user-visible change is a new
entry in /dev/dri but it is useless at the moment. This is a
first step to support render nodes [1].

The main benefit is to greatly reduce the diff with Linux (at the
expense of an unreadable commit diff). Hopefully, next upgrades will be
easier.

No updates were made to the drivers, beside adapting them to API
changes.

[1] https://en.wikipedia.org/wiki/Direct_Rendering_Manager#Render_nodes

Tested by: Many people
MFC after: 1 month
Relnotes: yes

Fix the incomplete conversion from atomic_t to long for test_bit().

Clarify confusions between atomic_t and bitmap. Fix bitmap operations
accordingly.

- Remove test_and_set_bit() macro. It is unused since r255037.
- Relax atomic_read() and atomic_set() macros. Linux does not require any
memory barrier. Also, these macros may be even reordered or optimized away
according to the API documentation:

https://www.kernel.org/doc/Documentation/atomic_ops.txt

drm: Update drm_atomic.h, now that projects/atomic64 is in HEAD

Submitted by: jkim@

Add the code for new Intel GPU driver, which supports GEM, KMS and
works with new generations of GPUs (IronLake, SandyBridge and
supposedly IvyBridge).

The driver is not connected to the build yet.

Sponsored by: The FreeBSD Foundation
MFC after: 1 week