mb/google/nissa/var/riven: add fw_config probe for storage devices

1. Add STORAGE_UNKNOWN fw_config to enable all storage devices,
this is used for the first boot in factory.

2. Add fw_config probe to enable/disable devices in devicetree
instead of variant.c, it can avoid suspend(s0ix) fail issue.

BUG=b:328580882
TEST=On riven eMMC and UFS SKUs, boot to OS and run
`suspend_stress_test -c 10` pass.

Change-Id: I518f1a5955fb88f304663112f1e3d4c744bde183
Signed-off-by: David Wu <david_wu@quanta.corp-partner.google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/83405
Reviewed-by: Subrata Banik <subratabanik@google.com>
Reviewed-by: Eric Lai <ericllai@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

0 files changed, 0 insertions, 0 deletions