[PATCH -next] PCI: endpoint: fix build error, EP NTB driver uses configfs

[Randy Dunlap]

The pci-epf-ntb driver uses configfs APIs, so it should depend on
CONFIGFS_FS to prevent build errors.

ld: drivers/pci/endpoint/functions/pci-epf-ntb.o: in function `epf_ntb_add_cfs':
pci-epf-ntb.c:(.text+0x1b): undefined reference to `config_group_init_type_name'

Fixes: 7dc64244f9e9 ("PCI: endpoint: Add EP function driver to provide NTB functionality")

Signed-off-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Kishon Vijay Abraham I <kishon@xxxxxx>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Cc: linux-pci@xxxxxxxxxxxxxxx
---
You may switch to 'select CONFIG_FS_FS' if you feel strongly about it.

 drivers/pci/endpoint/functions/Kconfig |    1 +
 1 file changed, 1 insertion(+)

--- linux-next-20210202.orig/drivers/pci/endpoint/functions/Kconfig
+++ linux-next-20210202/drivers/pci/endpoint/functions/Kconfig
@@ -16,6 +16,7 @@ config PCI_EPF_TEST
 config PCI_EPF_NTB
 	tristate "PCI Endpoint NTB driver"
 	depends on PCI_ENDPOINT
+	depends on CONFIGFS_FS
 	help
 	  Select this configuration option to enable the NTB driver
 	  for PCI Endpoint. NTB driver implements NTB controller