Minor comment cleanups.

lib/cretonne/src/abi.rs

@@ -162,7 +162,7 @@ pub fn legalize_abi_value(have: Type, arg: &ArgumentType) -> ValueConversion {
         }
         // We have the same number of bits as the argument.
         Ordering::Equal => {
-            // This must  be an integer vector that is split and then extended.
+            // This must be an integer vector that is split and then extended.
             assert!(arg.value_type.is_int());
             assert!(!have.is_scalar());
             ValueConversion::VectorSplit

lib/cretonne/src/licm.rs

@@ -97,7 +97,7 @@ fn create_pre_header(
 //
 // A loop header has a pre-header if there is only one predecessor that the header doesn't
 // dominate.
-// Returns the pre-header Ebb and the instruction jumping to  the header.
+// Returns the pre-header Ebb and the instruction jumping to the header.
 fn has_pre_header(
     layout: &Layout,
     cfg: &ControlFlowGraph,