[S] Change in coreboot[master]: mb/google/rex: Enable all DDI lanes

[Subrata Banik (Code Review)]

Attention is currently required from: Anil Kumar K, Tarun Tuli, Kapil Porwal.

Subrata Banik has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/74413 )

Change subject: mb/google/rex: Enable all DDI lanes
......................................................................

Patch Set 4:

(4 comments)

Commit Message:

https://review.coreboot.org/c/coreboot/+/74413/comment/b4c596be_13e22ae4 
PS4, Line 12: Branch=None
don't need, please drop

https://review.coreboot.org/c/coreboot/+/74413/comment/8298f6b3_757ff07c 
PS4, Line 12: Branch=None
Please add BUG=b:273901499

https://review.coreboot.org/c/coreboot/+/74413/comment/4cc2857e_d2020672 
PS4, Line 13: Test
TEST

https://review.coreboot.org/c/coreboot/+/74413/comment/5c3205e0_7cbfe318 
PS4, Line 13: rex
google/rex