In Valleyview the DPLL and lane control registers are accessible only
through side band fabric called DPIO. Added two tools to read and write
registers residing in this space.
v2: Moved the core read/write functions to lib/intel_dpio.c based on
Ben's feedback
Signed-off-by: Vijay Purushothaman <vijay.a.purushothaman@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>