rtlwifi: usb parts should depend on CONFIG_USB

ERROR: "usb_unanchor_urb" [drivers/net/wireless/rtlwifi/rtlwifi.ko] undefined!
ERROR: "usb_control_msg" [drivers/net/wireless/rtlwifi/rtlwifi.ko] undefined!
ERROR: "usb_submit_urb" [drivers/net/wireless/rtlwifi/rtlwifi.ko] undefined!
ERROR: "usb_get_dev" [drivers/net/wireless/rtlwifi/rtlwifi.ko] undefined!
ERROR: "usb_kill_anchored_urbs" [drivers/net/wireless/rtlwifi/rtlwifi.ko] undefined!
ERROR: "usb_put_dev" [drivers/net/wireless/rtlwifi/rtlwifi.ko] undefined!
ERROR: "usb_free_urb" [drivers/net/wireless/rtlwifi/rtlwifi.ko] undefined!
ERROR: "usb_anchor_urb" [drivers/net/wireless/rtlwifi/rtlwifi.ko] undefined!
ERROR: "usb_alloc_urb" [drivers/net/wireless/rtlwifi/rtlwifi.ko] undefined!
make[2]: *** [__modpost] Error 1
make[1]: *** [modules] Error 2
make: *** [sub-make] Error 2

The USB-part of rtlwifi should depend on CONFIG_USB.  This also
corrects the existing check for CONFIG_PCI to build pci.o.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rtlwifi/Makefile b/drivers/net/wireless/rtlwifi/Makefile
index 9192fd5..ec9393f 100644
--- a/drivers/net/wireless/rtlwifi/Makefile
+++ b/drivers/net/wireless/rtlwifi/Makefile
@@ -7,15 +7,18 @@
 		efuse.o		\
 		ps.o		\
 		rc.o		\
-		regd.o		\
-		usb.o
+		regd.o
 
 rtl8192c_common-objs +=		\
 
-ifeq ($(CONFIG_PCI),y)
+ifneq ($(CONFIG_PCI),)
 rtlwifi-objs	+= pci.o
 endif
 
+ifneq ($(CONFIG_USB),)
+rtlwifi-objs	+= usb.o
+endif
+
 obj-$(CONFIG_RTL8192C_COMMON)	+= rtl8192c/
 obj-$(CONFIG_RTL8192CE)		+= rtl8192ce/
 obj-$(CONFIG_RTL8192CU)		+= rtl8192cu/