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/usr/lib/udev/rules.d/75-net-description.rules

@@ -0,0 +1,14 @@
+# do not edit this file, it will be overwritten on update
+
+ACTION=="remove", GOTO="net_end"
+SUBSYSTEM!="net", GOTO="net_end"
+
+IMPORT{builtin}="net_id"
+
+SUBSYSTEMS=="usb", IMPORT{builtin}="usb_id", IMPORT{builtin}="hwdb --subsystem=usb"
+SUBSYSTEMS=="usb", GOTO="net_end"
+
+SUBSYSTEMS=="pci", ENV{ID_BUS}="pci", ENV{ID_VENDOR_ID}="$attr{vendor}", ENV{ID_MODEL_ID}="$attr{device}"
+SUBSYSTEMS=="pci", IMPORT{builtin}="hwdb --subsystem=pci"
+
+LABEL="net_end"