fix: Switch to space-separated sources.conf format

- Change from colon to space separation to avoid URL parsing issues
- Update sources.conf format: TYPE NAME URL VERSION BUILD_FUNCTION [EXTRA]
- Implement awk-based parsing for reliable field extraction
- Fix firmware package list (remove unavailable linux-firmware-marvell)

initramfs/etc/group

@@ -0,0 +1,35 @@
+root:x:0:root
+bin:x:1:root,bin,daemon
+daemon:x:2:root,bin,daemon
+sys:x:3:root,bin
+adm:x:4:root,daemon
+tty:x:5:
+disk:x:6:root
+lp:x:7:lp
+kmem:x:9:
+wheel:x:10:root
+floppy:x:11:root
+mail:x:12:mail
+news:x:13:news
+uucp:x:14:uucp
+cron:x:16:cron
+audio:x:18:
+cdrom:x:19:
+dialout:x:20:root
+ftp:x:21:
+sshd:x:22:
+input:x:23:
+tape:x:26:root
+video:x:27:root
+netdev:x:28:
+kvm:x:34:kvm
+games:x:35:
+shadow:x:42:
+www-data:x:82:
+users:x:100:games
+ntp:x:123:
+abuild:x:300:
+utmp:x:406:
+ping:x:999:
+nogroup:x:65533:
+nobody:x:65534: