[contextualprocess] QLatin1String -> QString

As Kevin pointed out, there's an extra conversion involved here --
although with -O3 the difference boils away leaving only a call
to a from-ASCII helper or a from-Latin1 helper.

While here, coding-style.

src/modules/contextualprocess/ContextualProcessJob.cpp

@@ -66,7 +66,7 @@ struct ContextualProcessBinding
     void append( const QString& value, CalamaresUtils::CommandList* commands )
     {
         checks.append( ValueCheck( value, commands ) );
-        if ( value == QLatin1Literal("*") )
+        if ( value == QString( "*" ) )
             wildcard = commands;
     }