coreboot_util: update SeaBIOS images to 4.9-Purism-2
- update coreboot repo tag to 4.9-Purism-2
- update hashes for pre-built 4.9-Purism-2 images
- update hashes for BIOS region when building from source
- update microcode hashes used when building from source
Signed-off-by: Matt DeVillier matt.devillier@puri.sm