[Serialization] Update DECL_LAST

Address post commit review at
llvm#119333 (review)

(cherry picked from commit 366dadd)

Author: ChuanqiXu9

clang/include/clang/Serialization/ASTBitCodes.h

@@ -1522,13 +1522,13 @@ enum DeclCode {
   /// An ImplicitConceptSpecializationDecl record.
   DECL_IMPLICIT_CONCEPT_SPECIALIZATION,
 
-  // A decls specilization record.
+  // A decls specialization record.
   DECL_SPECIALIZATIONS,
 
-  // A decls specilization record.
+  // A decls specialization record.
   DECL_PARTIAL_SPECIALIZATIONS,
 
-  DECL_LAST = DECL_IMPLICIT_CONCEPT_SPECIALIZATION
+  DECL_LAST = DECL_PARTIAL_SPECIALIZATIONS
 };
 
 /// Record codes for each kind of statement or expression.