Set MLIR_DISABLE_CONFIGURE_PYTHON_DEV_PACKAGES to disable MLIR python config. (#19328)

This is in preparation for
llvm/llvm-project#117934 and a followon patch
which changes the default python setup in a way that will conflict with
what we do. Landing pre-emptively to avoid disruption.

Signed-off-by: Stella Laurenzo <[email protected]>

Author: stellaraccident

build_tools/cmake/iree_llvm.cmake

@@ -161,6 +161,10 @@ macro(iree_llvm_set_bundled_cmake_options)
   set(MLIR_ENABLE_BINDINGS_PYTHON OFF CACHE BOOL "")
   set(MHLO_ENABLE_BINDINGS_PYTHON OFF CACHE BOOL "")
 
+  # Disable MLIR attempting to configure Python dev packages. We take care of
+  # that in IREE as a super-project.
+  set(MLIR_DISABLE_CONFIGURE_PYTHON_DEV_PACKAGES ON CACHE BOOL "" FORCE)
+
   # If we are building clang/lld/etc, these will be the targets.
   # Otherwise, empty so scripts can detect unavailability.
   set(IREE_CLANG_TARGET)