drm/i915: Import Linux commit 71244653a8fb0f46bc12ae421f1d5f72af6a75da

Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Mon Jun 4 18:39:20 2012 +0200

    drm/i915: adjusted_mode->clock in the dp mode_fixup

    ... instead of changing mode->clock, which we should leave as-is.

    After the previous patch we only touch that if it's a panel, and then
    adjusted mode->clock equals adjusted_mode->clock. Outside of
    intel_dp.c we only use ajusted_mode->clock in the mode_set functions.

    Within intel_dp.c we only use it to calculate the dp dithering
    and link bw parameters, so that's the only thing we need to fix
    up.

    As a temporary ugliness (until the cleanup in the next patch) we
    pass the adjusted_mode into dp_dither for both parameters (because
    that one still looks at mode->clock).

    Note that we do overwrite adjusted_mode->clock with the selected dp
    link clock, but that only happens after we've calculated everything we
    need based on the dotclock of the adjusted output configuration.

    Outside of intel_dp.c only intel_display.c uses adjusted_mode->clock,
    and that stays the same after this patch (still equals the selected dp
    link clock). intel_display.c also needs the actual dotclock (as
    target_clock), but that has been fixed up in the previous patch.

    v2: Adjust the debug message to also use adjusted_mode->clock.

    Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
    Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
    Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
drm: Const'ify the 1st "drm_display_mode" passed to "mode_fixup" callbacks

This will be needed by the Radeon KMS driver.
drm: Fix leak of connector->edid_blob_ptr
Add an mbuf pointer parameter to (*ext_free) to give the external
free function access to the mbuf the external memory was attached
to.

Mechanically adjust all users to include the mbuf parameter.

This fixes a long standing annoyance for external free functions.
Before one had to sacrifice one of the argument pointers for this.

Sponsored by:	The FreeBSD Foundation
Remove unnecessary setup of the m->pkthdr.header pointer.

Sponsored by:	The FreeBSD Foundation