compiler: fix a typo in comments

    
    Reviewed-on: https://go-review.googlesource.com/c/163097

From-SVN: r269049

gcc/go/gofrontend/MERGE

-08cd59a502127da776e076a8a37016a668ef27fa
+23f39fa450b84e81c5c39a7a840fcc88eeeea764
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.

gcc/go/gofrontend/types.h

@@ -3086,7 +3086,7 @@ class Interface_type : public Type
     return this->all_methods_ == NULL;
   }
 
-  // Return the list of locally defined methos.  This will return NULL
+  // Return the list of locally defined methods.  This will return NULL
   // for an empty interface.  Embedded interfaces will appear in this
   // list as an entry with no name.
   const Typed_identifier_list*