QCryptographicHash: give the result container a catchy name

Repeating QSmallByteArray<maxHashLength()> when reusing the type for
QMessageAuthenticationCode isn't DRY.

Pick-to: 6.5
Change-Id: I6d5ca2c14c5ea696a4d28eeb1fb384ff5671d161
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/tools/qcryptographichash.cpp

@@ -204,6 +204,8 @@ static constexpr int maxHashLength()
     return result;
 }
 
+using HashResult = QSmallByteArray<maxHashLength()>;
+
 #ifdef USING_OPENSSL30
 static constexpr const char * methodToName(QCryptographicHash::Algorithm method) noexcept
 {
@@ -301,7 +303,7 @@ public:
 #endif
     // protects result in finalize()
     QBasicMutex finalizeMutex;
-    QSmallByteArray<maxHashLength()> result;
+    HashResult result;
 
     const QCryptographicHash::Algorithm method;
 };