Add and correct comments.

Author: erikrose

crates/wasi-preview1-component-adapter/src/lib.rs

@@ -438,7 +438,7 @@ impl ImportAlloc {
 #[derive(Clone)]
 struct BumpAlloc {
     base: *mut u8,
-    len: usize,
+    len: usize, // remaining size available for allocation
 }
 
 impl BumpAlloc {

crates/wasmtime/src/runtime/component/linker.rs

@@ -168,7 +168,7 @@ impl<T: 'static> Linker<T> {
             imported_resources: Default::default(),
         };
 
-        // Walk over the component's list of import names and use that to lookup
+        // Walk over the component's list of import names and use that to look up
         // the definition within this linker that it corresponds to. When found
         // perform a typecheck against the component's expected type.
         let env_component = component.env_component();