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/configs/vexpress_aemv8a_semi_defconfig b/configs/vexpress_aemv8a_semi_defconfig
index cb04d19..7e5b53f 100644
--- a/configs/vexpress_aemv8a_semi_defconfig
+++ b/configs/vexpress_aemv8a_semi_defconfig
@@ -1,6 +1,7 @@
 CONFIG_ARM=y
 CONFIG_TARGET_VEXPRESS64_BASE_FVP=y
 CONFIG_SYS_MALLOC_F_LEN=0x2000
+CONFIG_IDENT_STRING=" vexpress_aemv8a"
 CONFIG_BOOTDELAY=1
 CONFIG_HUSH_PARSER=y
 CONFIG_SYS_PROMPT="VExpress64# "