Make {tablet, tablet_tool}::Info non-exhaustive

Almost forgot! Important for forwards-compatibility,
e.g. this new bus type thing on tablet which I haven’t added yet.

Author: chris-morgan

src/seat/tablet.rs

@@ -33,6 +33,7 @@ pub trait Handler: Sized {
 
 /// The description of a tablet device.
 #[derive(Debug, Default)]
+#[non_exhaustive]
 pub struct Info {
     /// The descriptive name of the tablet device.
     pub name: Option<String>,

src/seat/tablet_tool.rs

@@ -55,6 +55,7 @@ const HARDWARE_ID_WACOM: Capabilities = Capabilities::from_bits_retain(0b1000000
 
 /// Static information about the tool and its capabilities.
 #[derive(Clone, PartialEq, Eq)]
+#[non_exhaustive]
 pub struct Info {
     // Wish this was #[repr(u8)]… it’s wasting four bytes.
     r#type: Type,