SWDEV-232894 Port hipMemcpy optimizations from HCC to VDI

Apply the optimization to change for OpenCL too.
Clean up some unnecessary checks.

Change-Id: I840261fe35baeeadeba7388e86779d482f509aad

rocclr/device/rocm/rocblit.hpp

@@ -168,6 +168,8 @@ class DmaBlitManager : public device::HostBlitManager {
 
  protected:
   const static uint MaxPinnedBuffers = 4;
+  constexpr static size_t kMaxH2dMemcpySize = 8 * Ki;
+  constexpr static size_t kMaxD2hMemcpySize = 64; //!< 1 cacheline
 
   //! Synchronizes the blit operations if necessary
   inline void synchronize() const;