litex.build: update from migen.genlib.io litex.build.io.

litex_boards/targets/linsn_rv901t.py

@@ -6,7 +6,8 @@
 import argparse
 
 from migen import *
-from migen.genlib.io import DDROutput
+
+from litex.build.io import DDROutput
 
 from litex_boards.platforms import linsn_rv901t
 

litex_boards/targets/minispartan6.py

@@ -9,9 +9,10 @@ import argparse
 from fractions import Fraction
 
 from migen import *
-from migen.genlib.io import DDROutput
 from migen.genlib.resetsync import AsyncResetSynchronizer
 
+from litex.build.io import DDROutput
+
 from litex_boards.platforms import minispartan6
 
 from litex.soc.cores.clock import *