r8153_ecm: avoid to be prior to r8152 driver

Avoid r8153_ecm is compiled as built-in, if r8152 driver is compiled
as modules. Otherwise, the r8153_ecm would be used, even though the
device is supported by r8152 driver.

Fixes: c1aedf0 ("net/usb/r8153_ecm: support ECM mode for RTL8153")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/1394712342-15778-394-Taiwan-albertk@realtek.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/usb/Kconfig

@@ -628,4 +628,13 @@ config USB_NET_AQC111
 	  This driver should work with at least the following devices:
 	  * Aquantia AQtion USB to 5GbE
 
+config USB_RTL8153_ECM
+	tristate "RTL8153 ECM support"
+	depends on USB_NET_CDCETHER && (USB_RTL8152 || USB_RTL8152=n)
+	default y
+	help
+	  This option supports ECM mode for RTL8153 ethernet adapter, when
+	  CONFIG_USB_RTL8152 is not set, or the RTL8153 device is not
+	  supported by r8152 driver.
+
 endif # USB_NET_DRIVERS

drivers/net/usb/Makefile

@@ -13,7 +13,7 @@ obj-$(CONFIG_USB_LAN78XX)	+= lan78xx.o
 obj-$(CONFIG_USB_NET_AX8817X)	+= asix.o
 asix-y := asix_devices.o asix_common.o ax88172a.o
 obj-$(CONFIG_USB_NET_AX88179_178A)      += ax88179_178a.o
-obj-$(CONFIG_USB_NET_CDCETHER)	+= cdc_ether.o r8153_ecm.o
+obj-$(CONFIG_USB_NET_CDCETHER)	+= cdc_ether.o
 obj-$(CONFIG_USB_NET_CDC_EEM)	+= cdc_eem.o
 obj-$(CONFIG_USB_NET_DM9601)	+= dm9601.o
 obj-$(CONFIG_USB_NET_SR9700)	+= sr9700.o
@@ -41,3 +41,4 @@ obj-$(CONFIG_USB_NET_QMI_WWAN)	+= qmi_wwan.o
 obj-$(CONFIG_USB_NET_CDC_MBIM)	+= cdc_mbim.o
 obj-$(CONFIG_USB_NET_CH9200)	+= ch9200.o
 obj-$(CONFIG_USB_NET_AQC111)	+= aqc111.o
+obj-$(CONFIG_USB_RTL8153_ECM)	+= r8153_ecm.o