[MINOR][ML][MLLIB] Remove work around for breeze sparse matrix.

## What changes were proposed in this pull request?
Since we have updated breeze version to 0.12, we should remove work around for bug of breeze sparse matrix in v0.11.
I checked all mllib code and found this is the only work around for breeze 0.11.

## How was this patch tested?
Existing tests.

Author: Yanbo Liang <ybliang8@gmail.com>

Closes #14953 from yanboliang/matrices.

mllib-local/src/main/scala/org/apache/spark/ml/linalg/Matrices.scala

@@ -846,16 +846,8 @@ object Matrices {
       case dm: BDM[Double] =>
         new DenseMatrix(dm.rows, dm.cols, dm.data, dm.isTranspose)
       case sm: BSM[Double] =>
-        // Spark-11507. work around breeze issue 479.
-        val mat = if (sm.colPtrs.last != sm.data.length) {
-          val matCopy = sm.copy
-          matCopy.compact()
-          matCopy
-        } else {
-          sm
-        }
         // There is no isTranspose flag for sparse matrices in Breeze
-        new SparseMatrix(mat.rows, mat.cols, mat.colPtrs, mat.rowIndices, mat.data)
+        new SparseMatrix(sm.rows, sm.cols, sm.colPtrs, sm.rowIndices, sm.data)
       case _ =>
         throw new UnsupportedOperationException(
           s"Do not support conversion from type ${breeze.getClass.getName}.")

mllib/src/main/scala/org/apache/spark/mllib/linalg/Matrices.scala

@@ -983,16 +983,8 @@ object Matrices {
       case dm: BDM[Double] =>
         new DenseMatrix(dm.rows, dm.cols, dm.data, dm.isTranspose)
       case sm: BSM[Double] =>
-        // Spark-11507. work around breeze issue 479.
-        val mat = if (sm.colPtrs.last != sm.data.length) {
-          val matCopy = sm.copy
-          matCopy.compact()
-          matCopy
-        } else {
-          sm
-        }
         // There is no isTranspose flag for sparse matrices in Breeze
-        new SparseMatrix(mat.rows, mat.cols, mat.colPtrs, mat.rowIndices, mat.data)
+        new SparseMatrix(sm.rows, sm.cols, sm.colPtrs, sm.rowIndices, sm.data)
       case _ =>
         throw new UnsupportedOperationException(
           s"Do not support conversion from type ${breeze.getClass.getName}.")