targets: fomu: move SoCCore import definition

The SoCCore definition used to be available under litex.soc.integration,
however it was removed in
626533ce9d

Signed-off-by: Sean Cross <sean@xobs.io>

litex_boards/partner/targets/fomu.py

@@ -10,7 +10,7 @@ from migen import *
 from migen.genlib.resetsync import AsyncResetSynchronizer
 
 from litex.soc.cores import up5kspram
-from litex.soc.integration import SoCCore
+from litex.soc.integration.soc_core import SoCCore
 from litex.soc.integration.builder import Builder, builder_argdict, builder_args
 from litex.soc.integration.soc_core import soc_core_argdict, soc_core_args
 from litex.soc.integration.doc import AutoDoc