[coreboot-gerrit] Change in coreboot[master]: soc/intel/cmn/xhci: Add function to reset the XHCI controller

[Subrata Banik (Code Review)]

Attention is currently required from: Subrata Banik.
Hello build bot (Jenkins),

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/63551

to look at the new patch set (#2).

Change subject: soc/intel/cmn/xhci: Add function to reset the XHCI controller
......................................................................

soc/intel/cmn/xhci: Add function to reset the XHCI controller

This patch adds `xhci_host_reset()` to reset XHCI controller and the
scope of this function is with SMM hence, compiling xhci.c for SMM as
well.

Also, refactored `xhci.c` code to keep PCI enumeration within the scope
of `ramstage` alone hence, guarded with `ENV_RAMSTAGE` env_variable.

BUG=b:227289581
TEST=Able to perform a call from `xhci_host_reset` from S5 smi handler.

Signed-off-by: Subrata Banik 
Change-Id: Ie0dc0a64044f291893931726d26c08c8b964a3cc
---
M src/soc/intel/common/block/include/intelblocks/xhci.h
M src/soc/intel/common/block/xhci/Makefile.inc
M src/soc/intel/common/block/xhci/xhci.c
3 files changed, 28 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/51/63551/2