PnP - Added initial support for DigiRig v1.9 udev rules

overlay/etc/udev/rules.d/90-et-digirig-mobile.rules

@@ -0,0 +1,22 @@
+# Author   : Gaston Gonzalez
+# Date     : 30 September 2024
+# Purpose  : udev rules for the DigiRig Mobile v1.9 
+#
+# Preconditions:
+# 1. DigiRig Mobile  connected via USB cable
+# 2. This rule is processed after the IC-7200
+#
+# Postconditions:
+# 1. /dev/et-cat created
+# 
+
+# The IC-7200 uses the same chipsset. In order to avoid incorrect detection, we will check
+# for the presence of ET_DEVICE as the IC-7200 will set it as an earlier rule. With this
+# approach, the DigiRig Mobile rules must be processed later in the chain.
+SUBSYSTEM=="tty", ATTRS{idVendor}=="10c4", ATTRS{idProduct}=="ea60", ENV{ET_DEVICE}=="", \
+    ACTION=="add", \
+    ENV{SYSTEMD_WANTS}="", \
+    ENV{ET_DEVICE}="DIGIRIG_MOBILE", ENV{ET_SUBDEVICE}="CAT", GROUP="dialout", MODE="0660", SYMLINK+="et-cat"
+
+# TODO: Add rules for earlier 1.9 release
+# TODO: Add rules for sound card