xilinx: move microblaze-generic .dts to standard location

Aside from microblaze, all other SoCs/boards/vendors store their DT files
in board/$vendor/dts/$soc-$board.dts. Move microblaze-generic.dts to this
location for consistency.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
Acked-by: Michal Simek <monstr@monstr.eu>

board/xilinx/dts/microblaze.dts

-/include/ BOARD_DTS

include/configs/microblaze-generic.h

@@ -18,7 +18,7 @@
 /* Open Firmware DTS */
 #define CONFIG_OF_CONTROL	1
 #define CONFIG_OF_EMBED		1
-#define CONFIG_DEFAULT_DEVICE_TREE microblaze
+#define CONFIG_DEFAULT_DEVICE_TREE microblaze-generic
 
 /* linear and spi flash memory */
 #ifdef XILINX_FLASH_START