hwrng: iproc-rng200 - Add support for BCM7278

BCM7278 features a RNG200 hardware random number generator block, add
support for this chip by matching the chip-specific compatible string
and extending the Kconfig dependencies to allow building on ARCH_BRCMSTB
(base platform for 7278).
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/char/hw_random/Kconfig

@@ -100,12 +100,12 @@ config HW_RANDOM_BCM2835
 	  If unsure, say Y.
 
 config HW_RANDOM_IPROC_RNG200
-	tristate "Broadcom iProc RNG200 support"
-	depends on ARCH_BCM_IPROC
+	tristate "Broadcom iProc/STB RNG200 support"
+	depends on ARCH_BCM_IPROC || ARCH_BRCMSTB
 	default HW_RANDOM
 	---help---
 	  This driver provides kernel-side support for the RNG200
-	  hardware found on the Broadcom iProc SoCs.
+	  hardware found on the Broadcom iProc and STB SoCs.
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called iproc-rng200

drivers/char/hw_random/iproc-rng200.c

@@ -220,6 +220,7 @@ static int iproc_rng200_probe(struct platform_device *pdev)
 }
 
 static const struct of_device_id iproc_rng200_of_match[] = {
+	{ .compatible = "brcm,bcm7278-rng200", },
 	{ .compatible = "brcm,iproc-rng200", },
 	{},
 };