move some ConnectableWithClock instances to avoid orphan type class instance warning

Change-Id: I972e8e187f7cef35af84a7cfa4d145795ee1171c
Move the B2C conversion to PS7LIB.bsv

Change-Id: I4bc1a8dc9f4550af96a2028a43b7fb2d3df5ee04
updated bsv/ZynqTop.bsv now that mkPS7 converts the bits to clocks and resets

Change-Id: Idc62fc60ca5a87a6d3118a1efdd82d730591b921