[EMB-320] Enable config options for ZRAM

[bryanfoley]

Description

This PR enables kernel configuration options related to ZRAM, allowing ZRAM to be built and configured as part of the um-kernel configuration. This makes it possible to use compressed RAM-backed swap (and/or a compressed in-memory block device) on supported targets.

Why

ZRAM can improve system responsiveness under memory pressure by compressing pages in RAM instead of immediately paging out to slower storage. Enabling the relevant config options in the kernel provides the flexibility to turn ZRAM on where it’s beneficial and keep it off where it’s not needed.
What changed

• Enabled the required ZRAM kernel config options.
• Enabled/updated supporting options needed for ZRAM operation (e.g., swap and compression-related settings, where applicable).
• Ensured configuration is applied via the existing kernel config mechanism in this repository.

Impact / Risk

• Low to moderate risk: kernel config changes only.
• No behavioral change unless ZRAM is explicitly enabled/used in userspace.
• Potential impacts are primarily kernel size and feature surface area.

How has this been tested

Currently running on Falcon-34-POC as a long 2 day print job.

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