cxl/acpi: Fix CXL_ACPI and CXL_PMEM Kconfig tristate mismatch

Commit e7e222a ("cxl: Move devm_cxl_add_nvdimm_bridge() to
cxl_pmem.ko") moves devm_cxl_add_nvdimm_bridge() into the cxl_pmem file,
which has independent config compile options for built-in or module. The
call from cxl_acpi_probe() is guarded by IS_ENABLED(CONFIG_CXL_PMEM),
which evaluates to true for both =y and =m.

When CONFIG_CXL_PMEM=m, a built-in cxl_acpi attempts to reference a
symbol exported by a module, which fails to link. CXL_PMEM cannot simply
be promoted to =y in this configuration because it depends on LIBNVDIMM,
which may itself be =m.

Add a Kconfig dependency to prevent CXL_ACPI from being built-in when
CXL_PMEM is a module. This contrains CXL_ACPI to =m when CXL_PMEM=m,
while still allowing CXL_ACPI to be freely configured when CXL_PMEM is
either built-in or disabled.

[ dj: Fix up commit reference formatting. ]

Fixes: e7e222a ("cxl: Move devm_cxl_add_nvdimm_bridge() to cxl_pmem.ko")
Signed-off-by: Keith Busch <[email protected]>
Reviewed-by: Jonathan Cameron <[email protected]>
Reviewed-by: Dan Williams <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Dave Jiang <[email protected]>

Author: keithbusch

drivers/cxl/Kconfig

@@ -59,6 +59,7 @@ config CXL_ACPI
 	tristate "CXL ACPI: Platform Support"
 	depends on ACPI
 	depends on ACPI_NUMA
+	depends on CXL_PMEM || !CXL_PMEM
 	default CXL_BUS
 	select ACPI_TABLE_LIB
 	select ACPI_HMAT