nvmem: imx: scu: fix dependency in Kconfig

Fix below error by adding HAVE_ARM_SMCCC dependency in Kconfig
ERROR: "__arm_smccc_smc" [drivers/nvmem/nvmem-imx-ocotp-scu.ko] undefined!

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20191029114240.14905-9-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/nvmem/Kconfig

@@ -50,6 +50,7 @@ config NVMEM_IMX_OCOTP
 config NVMEM_IMX_OCOTP_SCU
 	tristate "i.MX8 SCU On-Chip OTP Controller support"
 	depends on IMX_SCU
+	depends on HAVE_ARM_SMCCC
 	help
 	  This is a driver for the SCU On-Chip OTP Controller (OCOTP)
 	  available on i.MX8 SoCs.