Staging: vt665?: prevent modules from being built into the kernel.

It causes lots of linking errors when both of these modules are built into the
kernel directly due to their global symbol mess.
Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/staging/vt6655/Kconfig

 config VT6655
    tristate "VIA Technologies VT6655 support"
-   depends on PCI && WLAN
+   depends on PCI && WLAN && m
    select WIRELESS_EXT
    select WEXT_PRIV
    ---help---

drivers/staging/vt6656/Kconfig

 config VT6656
 	tristate "VIA Technologies VT6656 support"
-	depends on USB && WLAN
+	depends on USB && WLAN && m
 	select WIRELESS_EXT
 	select WEXT_PRIV
 	select FW_LOADER