fix model specification with two liblinear models

[topepo]

correct:

>> $svmLinearWeights2$fit 
>> function (x, y, wts, param, lev, last, classProbs, ...) 
>> { 
>> model_type <- if (param$Loss == "L2") 
>> _2_ 
>> else _3_ 

For svmLinear3 it should be

>> > if(param$Loss == "L2") { 
>> >   model_type <- if(is.factor(y)) 2 else 12 
>> > } else model_type <- if(is.factor(y)) 3 else 13