PCI/DOE: Allow enabling DOE without CXL

PCIe devices (not CXL) can support DOE as well, so allow DOE to be enabled
even if CXL isn't.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alistair Francis <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Jonathan Cameron <[email protected]>

Author: alistair23

drivers/pci/Kconfig

@@ -122,7 +122,10 @@ config PCI_ATS
 	bool
 
 config PCI_DOE
-	bool
+	bool "Enable PCI Data Object Exchange (DOE) support"
+	help
+	  Say Y here if you want be able to communicate with PCIe DOE
+	  mailboxes.
 
 config PCI_ECAM
 	bool