nvmem: imx-ocotp: add COMPILE_TEST for proper test coverage

This patch add COMPILE_TEST to imx-ocotp driver so that it can be
compile tested on other platforms with zero day testing.
Also adds HAS_IOMEM dependancy as the users of devm_ioremap_resource()
which are compile-testable should depend on HAS_IOMEM.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/nvmem/Kconfig b/drivers/nvmem/Kconfig
index 5ff2189..f550c45 100644
--- a/drivers/nvmem/Kconfig
+++ b/drivers/nvmem/Kconfig
@@ -15,7 +15,8 @@
 
 config NVMEM_IMX_OCOTP
 	tristate "i.MX6 On-Chip OTP Controller support"
-	depends on SOC_IMX6
+	depends on SOC_IMX6 || COMPILE_TEST
+	depends on HAS_IOMEM
 	help
 	  This is a driver for the On-Chip OTP Controller (OCOTP) available on
 	  i.MX6 SoCs, providing access to 4 Kbits of one-time programmable