feat(pci): enable PCI for guests

[bchalios]

Add kernel configuration for enabling PCI support in microVMs. Configuration is taken from here:
https://github.com/firecracker-microvm/firecracker/blob/firecracker-v1.14/resources/guest_configs/pcie.config

Also, release this as a new (patch) kernel version so that we make deployment cleaner.

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Note

Medium Risk
Medium risk because it introduces new kernel configuration baselines (including PCI enablement) and the x86_64 config appears to be placed outside the expected configs/x86_64/ path, which could break builds or select the wrong config.

Overview
Adds new Linux 6.1.163 kernel config baselines for guests, with PCI support enabled for Firecracker microVMs (plus related options like CONFIG_VIRTIO_PCI, CONFIG_PCI_MSI, CONFIG_PCIEPORTBUS).

Introduces configs/arm64/6.1.163.config and a new x86_64 6.1.163 config file, but the x86_64 config is added as configs/6.1.163.config rather than under configs/x86_64/, which may not match the build script’s expected layout.

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PR Summary

Medium Risk
Kernel config changes can alter guest boot/runtime behavior and device compatibility, especially around PCI/virtio and IOMMU settings. Risk is moderate since the change is configuration-only but affects low-level platform capabilities.

Overview
Introduces new autogenerated kernel configuration files for 6.1.163-1.182.amzn2023 on x86_64 and arm64.

The configs explicitly enable PCI support for Firecracker microVMs (e.g., CONFIG_PCI, CONFIG_PCIEPORTBUS, CONFIG_VIRTIO_PCI, and related options), allowing guests to use PCI-backed virtio devices.

^{Written by Cursor Bugbot for commit 8a2885a. This will update automatically on new commits. Configure here.}