scripted-diff: s/WITH_MULTIPROCESS/ENABLE_IPC/ in cmake

Rename WITH_MULTIPROCESS to ENABLE_IPC, because ENABLE_IPC is a more accurate
name for the feature. It controls whether the src/ipc/ directory is built and
whether IPC features like -ipcbind, -ipcconnect, and -ipcfd are available. It
does NOT currently enable multiprocess features which are implemented in #10102
building on top of the IPC features. It will also no longer (as of the next
commit), control whether a find_package call is made so the "WITH_" prefix is
also inappropriate.

-BEGIN VERIFY SCRIPT-
git grep -l WITH_MULTIPROCESS | xargs sed -i s/WITH_MULTIPROCESS/ENABLE_IPC/g
-END VERIFY SCRIPT-

CMakePresets.json

@@ -81,7 +81,7 @@
         "ENABLE_WALLET": "ON",
         "WARN_INCOMPATIBLE_BDB": "OFF",
         "WITH_BDB": "ON",
-        "WITH_MULTIPROCESS": "ON",
+        "ENABLE_IPC": "ON",
         "WITH_QRENCODE": "ON",
         "WITH_USDT": "ON",
         "WITH_ZMQ": "ON"