PPC 85xx QEMU: Make a generic board file

This patch enables the E500 QEMU board to use the generic cross-arch board
infrastructure.

Signed-off-by: Alexander Graf <agraf@suse.de>
diff --git a/include/configs/qemu-ppce500.h b/include/configs/qemu-ppce500.h
index 10e014d..763a47a 100644
--- a/include/configs/qemu-ppce500.h
+++ b/include/configs/qemu-ppce500.h
@@ -19,6 +19,7 @@
 
 #undef CONFIG_SYS_TEXT_BASE
 #define CONFIG_SYS_TEXT_BASE	0xf01000 /* 15 MB */
+#define CONFIG_SYS_GENERIC_BOARD
 
 #define CONFIG_SYS_MPC85XX_NO_RESETVEC