don't import libblas (#133)

Author: jishnub

src/BlockBandedMatrices.jl

@@ -15,7 +15,7 @@ import Base.Broadcast: BroadcastStyle, AbstractArrayStyle, DefaultArrayStyle, Br
 import LinearAlgebra: UniformScaling, isdiag, rmul!, lmul!, ldiv!, rdiv!,
                         AbstractTriangular, AdjOrTrans, HermOrSym, StructuredMatrixStyle,
                         qr, qr!
-import LinearAlgebra.BLAS: BlasInt, BlasFloat, @blasfunc, libblas, BlasComplex, BlasReal
+import LinearAlgebra.BLAS: BlasInt, BlasFloat, @blasfunc, BlasComplex, BlasReal
 import LinearAlgebra.LAPACK: chktrans, chkdiag, liblapack, chklapackerror, checksquare, chkstride1,
                     chkuplo
 import MatrixFactorizations: ql, ql!, _ql, QLPackedQ, AdjQRPackedQLayout, AdjQLPackedQLayout, QR, QRPackedQ