Create gsi_x86 and gsi_x86_64 products

These gsi_$arch products are going to be used as GSI for compliance in S.
They are basically csi_$arch plus a few more modules needed for CTS, or
stripped-down versions of aosp_$arch.

Bug: 177495405
Test: $ lunch gsi_x86-userdebug; m
      $ lunch gsi_x86_64-userdebug; m
      # Mixed the system.img with aosp_cf_x86(_64)_phone and booted OK.
Change-Id: Ic59a0bfa95759c6e3cecf70668235632e3f94267
6 files changed