Install sof-firmware on Intel Panther Lake for DSP audio (#5606)

* Install sof-firmware on Intel Panther Lake for DSP audio

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* Need to have the sof-firmware package available during original offline install

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Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Co-authored-by: David Heinemeier Hansson <david@hey.com>

install/config/hardware/intel/sof-firmware.sh

@@ -0,0 +1,8 @@
+# Install Sound Open Firmware for the audio DSP on non-XPS Intel Panther
+# Lake systems. XPS PTL stays on linux-ptl, which hard-deps sof-firmware.
+# Mainline `linux` only optdeps it, so without this the DSP fails to boot
+# and only auto_null shows up in PipeWire.
+
+if omarchy-hw-intel-ptl && ! omarchy-hw-match "XPS"; then
+  omarchy-pkg-add sof-firmware
+fi