fix: fix raspicam detection

if `start_x=1` is not set,
it messes up output of `vcgencmd get_camera`.

Which leads to not detected libcamera csi cams,
even if they are detected correctly

Therefor using libcamera-hello to determine if available

Signed-off-by: Stephan Wendel <me@stephanwe.de>

libs/hwhandler.sh

@@ -60,9 +60,9 @@ list_cam_v4l2ctrls() {
 
 ## Determine connected libcamera (CSI) device
 detect_libcamera() {
-    local avail
-    if [[ "$(is_raspberry_pi)" = "1" ]]; then
-        vcgencmd get_camera | grep -c "libcamera interfaces=1" || true
+    if [[ "$(is_raspberry_pi)" = "1" ]] &&
+    [[ -x "$(command -v libcamera-hello)" ]]; then
+        libcamera-hello --list-cameras | awk 'NR==1 {print $1}' | grep -c "Available"
     fi
 }