remove unnecessary output from lda native

[frank-dong-ms-zz]

issue: #3192

these output looks like debug info and don't need output them

[codecov]

Codecov Report

Merging #5259 into master will increase coverage by 0.07%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #5259      +/-   ##
==========================================
+ Coverage   73.49%   73.57%   +0.07%     
==========================================
  Files        1014     1014              
  Lines      188680   188680              
  Branches    20330    20330              
==========================================
+ Hits       138677   138814     +137     
+ Misses      44493    44369     -124     
+ Partials     5510     5497      -13     

Flag	Coverage Δ
#Debug	73.57% <ø> (+0.07%)	⬆️
#production	69.39% <ø> (+0.09%)	⬆️
#test	87.43% <ø> (ø)

Impacted Files	Coverage Δ
...rosoft.ML.AutoML/ColumnInference/TextFileSample.cs	59.60% <0.00%> (-2.65%)	⬇️
src/Microsoft.ML.Maml/MAML.cs	23.78% <0.00%> (-2.43%)	⬇️
src/Microsoft.ML.Data/Utils/LossFunctions.cs	67.35% <0.00%> (+0.51%)	⬆️
...oft.ML.StandardTrainers/Standard/SdcaMulticlass.cs	92.49% <0.00%> (+1.02%)	⬆️
...soft.ML.Transforms/Text/WordEmbeddingsExtractor.cs	86.87% <0.00%> (+1.13%)	⬆️
...crosoft.ML.StandardTrainers/Optimizer/Optimizer.cs	73.12% <0.00%> (+1.15%)	⬆️
src/Microsoft.ML.Sweeper/AsyncSweeper.cs	72.60% <0.00%> (+1.36%)	⬆️
...L.AutoML/TrainerExtensions/TrainerExtensionUtil.cs	86.36% <0.00%> (+1.65%)	⬆️
...crosoft.ML.StandardTrainers/Standard/SdcaBinary.cs	88.31% <0.00%> (+3.24%)	⬆️
src/Microsoft.ML.Data/Training/TrainerUtils.cs	69.67% <0.00%> (+3.81%)	⬆️
... and 1 more

[mstfbl]