Added const to new functions

src/macros.rs

@@ -88,7 +88,7 @@ macro_rules! plic_context {
 
         impl $PLIC {
             /// Creates a new PLIC context interface.
-            pub fn new() -> Self {
+            pub const fn new() -> Self {
                 Self {
                     context: $crate::peripheral::PLIC::new(),
                 }

src/peripheral.rs

@@ -36,7 +36,7 @@ impl<const BASE: usize, const CONTEXT: usize> PLIC<BASE, CONTEXT> {
 
     /// Creates a new interface for the PLIC peripheral. PACs can use this
     /// function to add a PLIC interface to their `Peripherals` struct.
-    pub fn new() -> Self {
+    pub const fn new() -> Self {
         Self {
             _marker: PhantomData,
         }