mb/google/brya/var/vell: select SOC_INTEL_RAPTORLAKE

mb/google/brya/var/vell: select SOC_INTEL_RAPTORLAKE

Select SOC_INTEL_RAPTORLAKE to force coreboot to use the RPL FSP headers
for FSP as vell is using a converged firmware image.

This effort also helps to save vell boot time by 80-100ms as RPL FSP is
better optimized.

Additionally, Raptor Lake platform only needs 1 SIPI-SIPI which saves
10ms of the boot time.

BUG=b:352330495
TEST=Able to build and boot google/vell.

warm reboot time w/o this CL

```
Total Time: 1,408,669
```

warm reboot time w/ this CL

```
Total Time: 1,235,651
```

Change-Id: I8f7dd76f00cfeff2908aeb805524706ac23403fa
Signed-off-by: Subrata Banik <subratabanik@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/84491
Reviewed-by: Eric Lai <ericllai@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>