Single XML package rather than one per platform

This saves us a *lot* of copy&pasted build foo and replaces it with a couple
of config options that can be set in menuconfig.

This makes adding a new platform a much smaller operation, requiring fewer
changes that are scattered throughout the buildroot tree.

Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>
diff --git a/openpower/configs/romulus_defconfig b/openpower/configs/romulus_defconfig
index 84733b1..7e6b791 100644
--- a/openpower/configs/romulus_defconfig
+++ b/openpower/configs/romulus_defconfig
@@ -43,7 +43,6 @@
 BR2_HOSTBOOT_CONFIG_FILE="romulus.config"
 BR2_OPENPOWER_PNOR_XML_LAYOUT_FILENAME="defaultPnorLayout_64.xml"
 BR2_OPENPOWER_CONFIG_NAME="romulus"
-BR2_OPENPOWER_XML_PACKAGE="romulus-xml"
 BR2_OPENPOWER_PNOR_FILENAME="romulus.pnor"
 #BR2_OPENPOWER_PNOR_UPDATE_FILENAME="romulus_update.pnor"
 BR2_HOSTBOOT_BINARY_SBE_FILENAME="nimbus_sbe.img.ecc"
@@ -61,6 +60,10 @@
 BR2_SKIBOOT_CUSTOM_VERSION=y
 BR2_SKIBOOT_CUSTOM_VERSION_VALUE="f0ebbc8318e64870a68d337e77b0257678c2b055"
 BR2_PACKAGE_LOADKEYS=y
-BR2_ROMULUS_SYSTEM_XML_FILENAME="ROMULUS_hb.system.xml"
-BR2_ROMULUS_MRW_XML_FILENAME="ROMULUS_hb.mrw.xml"
-BR2_ROMULUS_BIOS_XML_FILENAME="ROMULUS_bios.xml"
+BR2_OPENPOWER_MACHINE_XML_GITHUB_PROJECT=y
+BR2_OPENPOWER_MACHINE_XML_GITHUB_PROJECT_VALUE="romulus-xml"
+BR2_OPENPOWER_MACHINE_XML_VERSION="301279cbdb3595ad1bbdce4d9d2189db0470a62a"
+BR2_OPENPOWER_MACHINE_XML_FILENAME="romulus.xml"
+BR2_OPENPOWER_SYSTEM_XML_FILENAME="ROMULUS_hb.system.xml"
+BR2_OPENPOWER_MRW_XML_FILENAME="ROMULUS_hb.mrw.xml"
+BR2_OPENPOWER_BIOS_XML_FILENAME="ROMULUS_bios.xml"