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-

CMakeLists.txt

@@ -153,8 +153,8 @@ endif()
 
 cmake_dependent_option(WITH_DBUS "Enable DBus support." ON "CMAKE_SYSTEM_NAME STREQUAL \"Linux\" AND BUILD_GUI" OFF)
 
-option(WITH_MULTIPROCESS "Build multiprocess bitcoin-node and bitcoin-gui executables in addition to monolithic bitcoind and bitcoin-qt executables. Requires libmultiprocess library. Experimental." OFF)
-if(WITH_MULTIPROCESS)
+option(ENABLE_IPC "Build multiprocess bitcoin-node and bitcoin-gui executables in addition to monolithic bitcoind and bitcoin-qt executables. Requires libmultiprocess library. Experimental." OFF)
+if(ENABLE_IPC)
   find_package(Libmultiprocess REQUIRED COMPONENTS Lib)
   find_package(LibmultiprocessNative REQUIRED COMPONENTS Bin
     NAMES Libmultiprocess
@@ -648,14 +648,14 @@ message("Configure summary")
 message("=================")
 message("Executables:")
 message("  bitcoind ............................ ${BUILD_DAEMON}")
-if(BUILD_DAEMON AND WITH_MULTIPROCESS)
+if(BUILD_DAEMON AND ENABLE_IPC)
   set(bitcoin_daemon_status ON)
 else()
   set(bitcoin_daemon_status OFF)
 endif()
 message("  bitcoin-node (multiprocess) ......... ${bitcoin_daemon_status}")
 message("  bitcoin-qt (GUI) .................... ${BUILD_GUI}")
-if(BUILD_GUI AND WITH_MULTIPROCESS)
+if(BUILD_GUI AND ENABLE_IPC)
   set(bitcoin_gui_status ON)
 else()
   set(bitcoin_gui_status OFF)