Create AniMe device only if physical device exists

The call to create the device handler will return with an error if
the physical device doesn't exist, the device (if exists) is stored
in an option already so just keep that as `None` if errored.

Addresses issue #14

README.md

@@ -99,6 +99,10 @@ sudo systemctl enable rog-core.service
 
 Thanks to @aspann you can grab it here [sys-power/rog-core](https://lab.retarded.farm/zappel/zGentoo/-/tree/master/sys-power/rog-core)
 
+### Arch AUR
+
+You can find the thingimajig [here](https://aur.archlinux.org/packages/rog-core/)
+
 ## Updating
 
 Occasionally I might break things for you by tweaking or changing the config file layout. Usually this will mean you

rog-core/src/animatrix_control.rs

@@ -33,7 +33,7 @@ impl AniMeWriter {
     pub fn new() -> Result<AniMeWriter, Box<dyn Error>> {
         // We don't expect this ID to ever change
         let mut dev_handle = AniMeWriter::get_device(0x0b05, 0x193b).map_err(|err| {
-            error!("Could not get device handle: {:?}", err);
+            error!("Could not get AniMe display handle: {:?}", err);
             err
         })?;
         // This config seems to be the required device config for writing

rog-core/src/daemon.rs

@@ -69,8 +69,10 @@ pub async fn start_daemon() -> Result<(), Box<dyn Error>> {
     // Possible Animatrix
     let mut animatrix_writer = None;
     if laptop.support_animatrix() {
-        animatrix_writer = Some(AniMeWriter::new()?);
-        info!("Device has an AniMe Matrix display");
+        if let Ok(dev) = AniMeWriter::new() {
+            animatrix_writer = Some(dev);
+            info!("Device has an AniMe Matrix display");
+        }
     }
 
     // Set up the mutexes