Akeem Abodunrin authored Feb 27, 2020 and Petri Latvala committed Feb 27, 2020

This patch adds script and applicable assembly sources, so that we can use
igt to assemble Clear Batch Buffer kernel for gen7 and gen7.5 devices -
Resultant header files would be imported to i915, and used as they are...

With this patch, user need to have mesa configured on their platform,
before igt could be used to achieve the purpose of assembling the kernel
from source.

This is needed for "Security mitigation for Intel Gen7/7.5 HWs"
Intel ID: PSIRT-TA-201910-001/CVEID: CVE-2019-14615

v2: Addressed formatting, -g option and other minor issues (Petri)
v3: Update script due to suggested changes in i915, and Mesa tool
v4: Update help comment with Mesa build option with meson (Petri)
v5: Modify how user specify i965_asm - script now takes binary, instead
of Mesa tool source directory (Ville).
v6: Update script to reflect Mesa tool final changes to assemble CB
kernel - and renamed files based on Petri's suggestion...

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Petri Latvala <petri.latvala@intel.com>
Cc: Bloomfield Jon <jon.bloomfield@intel.com>
Signed-off-by: Akeem G Abodunrin <akeem.g.abodunrin@intel.com>
Reviewed-by: Petri Latvala <petri.latvala@intel.com>