drm/i915: Inline intel_suspend_complete

Initially we thought that the platform specific suspend/resume sequences
can be shared between the runtime and system suspend/resume handlers.
This turned out to be not true, we have quite a few differences on most
of the platforms. This was realized already earlier by Paulo who
inlined the platform specific resume_prepare handlers. We have the
same problem with the corresponding suspend_complete handlers, there are
platform differences that make it unfeasible to share the code between
the runtime and system suspend paths. Also now we call functions that
need to be paired like hsw_enable_pc8()/hsw_disable_pc8() from different
levels of the call stack, which is confusing. Fix this by inlining the
suspend_complete handlers too.

This is also needed by the next patch that removes a redundant
uninit/init call during system suspend/resume on BXT.

No functional change.

CC: Paulo Zanoni <przanoni@gmail.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Bob Paauwe <bob.j.paauwe@intel.com>
[s/uninline/inline in the commit message]
Link: http://patchwork.freedesktop.org/patch/msgid/1461173277-16090-2-git-send-email-imre.deak@intel.com