fcc-unlock: Case-insensitive grep for identifying MBIM or AT port

Signed-off-by: Jongmin Kim <jmkim@debian.org>

data/dispatcher-fcc-unlock/105b

@@ -22,8 +22,8 @@ for PORT in "$@"; do
   # match port type in Linux 5.14 and newer
   grep -q MBIM "/sys/class/wwan/$PORT/type" 2>/dev/null ||
   # match port name in Linux 5.13
-  echo "$PORT" | grep -q MBIM && {
-    MBIM_PORT=$PORT
+  echo "$PORT" | grep -qi MBIM && {
+    MBIM_PORT="$PORT"
     break
   }
 done

data/dispatcher-fcc-unlock/14c3

@@ -22,8 +22,8 @@ for PORT in "$@"; do
   # match port type in Linux 5.14 and newer
   grep -q AT "/sys/class/wwan/$PORT/type" 2>/dev/null ||
   # match port name in Linux 5.13
-  echo "$PORT" | grep -q AT && {
-    AT_PORT=$PORT
+  echo "$PORT" | grep -qi AT && {
+    AT_PORT="$PORT"
     break
   }
 done
@@ -31,7 +31,7 @@ done
 # fail if no AT port exposed
 [ -n "$AT_PORT" ] || exit 2
 
-DEVICE=/dev/${AT_PORT}
+DEVICE="/dev/$AT_PORT"
 
 at_command() {
     exec 99<>"$DEVICE"