wireguard: Kconfig: select CRYPTO_CHACHA_S390

Select the new implementation of CHACHA20 for S390 when available.
It is faster than the generic software implementation, but also prevents
some linker errors in certain situations.
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/linux-kernel/202207030630.6SZVkrWf-lkp@intel.com/Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/Kconfig

@@ -94,6 +94,7 @@ config WIREGUARD
 	select CRYPTO_CURVE25519_NEON if ARM && KERNEL_MODE_NEON
 	select CRYPTO_CHACHA_MIPS if CPU_MIPS32_R2
 	select CRYPTO_POLY1305_MIPS if MIPS
+	select CRYPTO_CHACHA_S390 if S390
 	help
 	  WireGuard is a secure, fast, and easy to use replacement for IPSec
 	  that uses modern cryptography and clever networking tricks. It's