CXL: daxctl online all memory by default

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2168268

This MR pushes forward the CXL kernel support in RHEL9 to remain consistent with upstream CXL-related commits through e9ee9fe3a9d4a. The partner requesting this functionality verified test kernels with this patchset applied provided satisfactory results.

  cxl/pci: Move tracepoint definitions to drivers/cxl/core/
  cxl/region: Only warn about cpu_cache_invalidate_memregion() once
  tools/testing/cxl: Prevent cxl_test from confusing production modules
  cxl/pci: Show opcode in debug messages when sending a command
  tools/testing/cxl: require 64-bit
  cxl/region: Clarify when a cxld->commit() callback is mandatory
  cxl/port: Link the 'parent_dport' in portX/ and endpointX/ sysfs
  cxl/region: Add a mode attribute for regions
  cxl/region: Support empty uuids for non-pmem regions
  cxl/region: Validate region mode vs decoder mode
  cxl/region: Add volatile region creation support
  cxl/region: Refactor attach_target() for autodiscovery
  cxl/region: Move region-position validation to a helper
  kernel/range: Uplevel the cxl subsystem's range_contains() helper
  cxl/region: Enable CONFIG_CXL_REGION to be toggled
  redhat/configs: Enable CONFIG_CXL_REGION
  cxl/port: Split endpoint and switch port probe
  cxl/region: Add region autodiscovery
  tools/testing/cxl: Define a fixed volatile configuration to parse
  dax/hmem: Convey the dax range via memregion_info()
  dax: Assign RAM regions to memory-hotplug by default
  cxl: avoid returning uninitialized error code
  cxl/port: Fix find_cxl_root() for RCDs and simplify it
  cxl/region: Fix region setup/teardown for RCDs
  cxl/region: Move coherence tracking into cxl_region_attach()

Signed-off-by: John W. Linville linville@redhat.com