staging/wlan-ng: add CRC32 dependency in Kconfig

wlan-ng uses the function crc32_le,
but CRC32 wasn't a dependency of wlan-ng

Co-developed-by: Michael Kupfer <michael.kupfer@fau.de>
Signed-off-by: Michael Kupfer <michael.kupfer@fau.de>
Signed-off-by: Kay Friedrich <kay.friedrich@fau.de>
Link: https://lore.kernel.org/r/20191127112457.2301-1-kay.friedrich@fau.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/wlan-ng/Kconfig

@@ -4,6 +4,7 @@ config PRISM2_USB
 	depends on WLAN && USB && CFG80211
 	select WIRELESS_EXT
 	select WEXT_PRIV
+	select CRC32
 	help
 	  This is the wlan-ng prism 2.5/3 USB driver for a wide range of
 	  old USB wireless devices.