BB retimer: Do not need B16 to be set for USB4 mode
BB retimer: Do not need B16 to be set for USB4 mode

Retimer bit16 is don't care for USB4 mode, so do not update it

BUG=None
BRANCH=None
TEST=Tested on voxel, USB4 enumerates fine.

Signed-off-by: Ayushee Shah <5730d7ed61dc96fa04bcc2bc2e4ce32af5b2c19d@intel.com>
Change-Id: I4e161542cd6eeda5b595cf3c071aafe71b8754cb
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2719197
Reviewed-by: Vijay P Hiremath <006c712879a3af08bfdb5c2b8491a8b2d5fd73cd@intel.com>
Reviewed-by: Keith Short <f6d578f97033c25f1206cb57d52f358974c82954@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec