drm/i915: Don't trust CSR program memory contents

Replaces "drm/i915: Force loading of csr program at boot" in the old
series.

Previously we called blindly into intel_csr_load_program() and depended
on a check of whether the CSR program memory was cleared or not.
This check is not reliable and no longer needed since we fixed the
call-sites of intel_csr_load_program().

Signed-off-by: Patrik Jakobsson <patrik.jakobsson@linux.intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447084107-8521-2-git-send-email-patrik.jakobsson@linux.intel.com