cxl: Add CONFIG_CXL_EEH symbol

CONFIG_CXL_EEH is for CXL's EEH related code.

Other drivers can depend on or #ifdef on this symbol to configure
PERST behaviour, allowing CXL to participate in the EEH process.
Reviewed-by: NCyril Bur <cyrilbur@gmail.com>
Signed-off-by: NDaniel Axtens <dja@axtens.net>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>

drivers/misc/cxl/Kconfig

@@ -11,11 +11,16 @@ config CXL_KERNEL_API
 	bool
 	default n
 
+config CXL_EEH
+	bool
+	default n
+
 config CXL
 	tristate "Support for IBM Coherent Accelerators (CXL)"
-	depends on PPC_POWERNV && PCI_MSI
+	depends on PPC_POWERNV && PCI_MSI && EEH
 	select CXL_BASE
 	select CXL_KERNEL_API
+	select CXL_EEH
 	default m
 	help
 	  Select this option to enable driver support for IBM Coherent