thunderbolt: select CRC32 in Kconfig

We use __crc32c_le in ctl.c. So make sure that the dependency is there.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NAndreas Noever <andreas.noever@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/thunderbolt/Kconfig

 menuconfig THUNDERBOLT
 	tristate "Thunderbolt support for Apple devices"
 	depends on PCI
+	select CRC32
 	help
 	  Cactus Ridge Thunderbolt Controller driver
 	  This driver is required if you want to hotplug Thunderbolt devices on