aspeed: add AST2500 evaluation board target

There currently aren't any usable targets provided with meta-aspeed.
Typical OE BSP layers provide reference metadata for evaluation boards.
Provide one for the AST2500 evaluation board.

Typical BSPs also provide an image class that produces images usable on
the target hardware.  meta-aspeed doesn't have one (yet), so although
baking an image (e.g. core-image-minimal) will now work, it will not
produce images usable with actual Aspeed hardware.

Change-Id: Id066a34e65a365cbec5b35c5eef4e1a9d9a0ec02
Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
diff --git a/conf/machine/evb-ast2500.conf b/conf/machine/evb-ast2500.conf
new file mode 100644
index 0000000..81365d4
--- /dev/null
+++ b/conf/machine/evb-ast2500.conf
@@ -0,0 +1,8 @@
+KMACHINE = "aspeed"
+KERNEL_DEVICETREE = "${KMACHINE}-ast2500-evb.dtb"
+
+UBOOT_MACHINE = "ast_g5_phy_config"
+
+FLASH_SIZE = "32768"
+
+require conf/machine/include/ast2500.inc