simplify unsafe_resize in matrix resizedata (#433)

Author: jishnub

src/Caching/matrix.jl

@@ -11,12 +11,8 @@ function resizedata!(B::CachedOperator{T,Matrix{T}},n::Integer,m::Integer) where
 
     # this does nothing if already in dimensions
     N,M=size(B.data)
-    if n > N && m > M
-        B.data = unsafe_resize!(B.data,n,m)
-    elseif n > N
-        B.data = unsafe_resize!(B.data,n,:)
-    elseif m > M
-        B.data = unsafe_resize!(B.data,:,m)
+    if !(n < N && m < M)
+        B.data = unsafe_resize!(B.data,max(n,N),max(m,M))
     end
 
     if n ≤ B.datasize[1] && m ≤ B.datasize[2]

src/LinearAlgebra/helper.jl

@@ -174,7 +174,6 @@ function mindotu(a::AbstractVector,b::AbstractVector)
 end
 
 
-# efficiently resize a Matrix.  Note it doesn't change the input ptr
 function unsafe_resize!(W::AbstractMatrix,::Colon,m::Integer)
     if m == size(W,2)
         W