Kconfig: Move config IDENT_STRING to Kconfig

Move the config IDENT_STRING to Kconfig and migrate all boards

[sivadur: Migrate zynq boards]
Signed-off-by: Siva Durga Prasad Paladugu <sivadur@xilinx.com>
[trini: Update configs, add some default to sunxi Kconfig]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/board/sunxi/Kconfig b/board/sunxi/Kconfig
index 79f644a..b139d1c 100644
--- a/board/sunxi/Kconfig
+++ b/board/sunxi/Kconfig
@@ -1,5 +1,8 @@
 if ARCH_SUNXI
 
+config IDENT_STRING
+	default " Allwinner Technology"
+
 config SPL_GPIO_SUPPORT
 	default y