hwrng: Kconfig - Do not enable by default CN10K driver

Do not enable by default the CN10K HW random generator driver.

CN10K Random Number Generator is available only on some specific
Marvell SoCs, however the driver is in practice enabled by default on
all arm64 configs.
Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/char/hw_random/Kconfig

@@ -555,7 +555,6 @@ config HW_RANDOM_ARM_SMCCC_TRNG
 config HW_RANDOM_CN10K
        tristate "Marvell CN10K Random Number Generator support"
        depends on HW_RANDOM && PCI && (ARM64 || (64BIT && COMPILE_TEST))
-       default HW_RANDOM
        help
 	 This driver provides support for the True Random Number
 	 generator available in Marvell CN10K SoCs.