aspeed: enable 'hw-rng' MACHINE_FEATURE

Change Iee340ffd294c4f40ba3360acd3f750d886865608 introduced a
machine feature which communicates to recipes if a hw random
number generator is present.  Since the Aspeed chips have a
supported RNG, enable this MACHINE_FEATURE.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I53125facd2f4ce2724e2fbb7224e4e3b6d27a9fa
diff --git a/conf/machine/include/aspeed.inc b/conf/machine/include/aspeed.inc
index c30eb6b..fdc4119 100644
--- a/conf/machine/include/aspeed.inc
+++ b/conf/machine/include/aspeed.inc
@@ -23,6 +23,7 @@
 IMAGE_BOOT_FILES ?= "fitImage-${INITRAMFS_IMAGE}-${MACHINE}-${MACHINE};fitImage"
 
 MACHINE_EXTRA_RRECOMMENDS += "udev-aspeed-vuart udev-aspeed-mtd-partitions"
+MACHINE_FEATURES += "hw-rng"
 
 MACHINEOVERRIDES =. "aspeed:"