hwrng: ppc4xx - add support for ppc4xx TRNG

Various PowerPC 4xx SoCs contain a TRNG embedded in the Security function.
This adds a device driver for that TRNG.

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile
index 3db4eb8..c88f244 100644
--- a/drivers/char/hw_random/Makefile
+++ b/drivers/char/hw_random/Makefile
@@ -20,3 +20,4 @@
 obj-$(CONFIG_HW_RANDOM_OCTEON) += octeon-rng.o
 obj-$(CONFIG_HW_RANDOM_NOMADIK) += nomadik-rng.o
 obj-$(CONFIG_HW_RANDOM_PICOXCELL) += picoxcell-rng.o
+obj-$(CONFIG_HW_RANDOM_PPC4XX) += ppc4xx-rng.o