{,_}tools→{,_}utils

In context of nMigen, "tools" means "parts of toolchain", so it is
confusing to have a completely unrelated module also called "tools".

nmigen/compat/genlib/cdc.py

@@ -1,6 +1,6 @@
 import warnings
 
-from ..._tools import deprecated
+from ..._utils import deprecated
 from ...lib.cdc import FFSynchronizer as NativeFFSynchronizer
 from ...hdl.ast import *
 from ..fhdl.module import CompatModule

nmigen/compat/genlib/fifo.py

@@ -1,4 +1,4 @@
-from ..._tools import deprecated, extend
+from ..._utils import deprecated, extend
 from ...lib.fifo import (FIFOInterface as NativeFIFOInterface,
   SyncFIFO as NativeSyncFIFO, SyncFIFOBuffered as NativeSyncFIFOBuffered,
   AsyncFIFO as NativeAsyncFIFO, AsyncFIFOBuffered as NativeAsyncFIFOBuffered)

nmigen/compat/genlib/fsm.py

@@ -1,6 +1,6 @@
 from collections import OrderedDict
 
-from ..._tools import deprecated, _ignore_deprecated
+from ..._utils import deprecated, _ignore_deprecated
 from ...hdl.xfrm import ValueTransformer, StatementTransformer
 from ...hdl.ast import *
 from ..fhdl.module import CompatModule, CompatFinalizeError

nmigen/compat/genlib/resetsync.py

@@ -1,4 +1,4 @@
-from ..._tools import deprecated
+from ..._utils import deprecated
 from ...lib.cdc import ResetSynchronizer as NativeResetSynchronizer