linux-postmarketos-qcom-sc7180: enable zstd firmware compression support
Needed for https://gitlab.alpinelinux.org/alpine/aports/-/merge_requests/60282 as acer-aspire1 uses linux-firmware.
Needed for https://gitlab.alpinelinux.org/alpine/aports/-/merge_requests/60282 as acer-aspire1 uses linux-firmware.