ARM: remove redudant information from Kconfig files

- "string" type for SYS_* is defined in arch/Kconfig
 - SYS_CPU "armv7" has been replaced with "select CPU_V7"
 - SYS_SOC "tegra124" is already defined in tegra124/Kconfig

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Bo Shen <voice.shen@atmel.com>
diff --git a/board/atmel/sama5d4_xplained/Kconfig b/board/atmel/sama5d4_xplained/Kconfig
index f6440c0..f320a68 100644
--- a/board/atmel/sama5d4_xplained/Kconfig
+++ b/board/atmel/sama5d4_xplained/Kconfig
@@ -1,8 +1,5 @@
 if TARGET_SAMA5D4_XPLAINED
 
-config SYS_CPU
-	default "armv7"
-
 config SYS_BOARD
 	default "sama5d4_xplained"
 
diff --git a/board/atmel/sama5d4ek/Kconfig b/board/atmel/sama5d4ek/Kconfig
index a889895..7dc569c 100644
--- a/board/atmel/sama5d4ek/Kconfig
+++ b/board/atmel/sama5d4ek/Kconfig
@@ -1,8 +1,5 @@
 if TARGET_SAMA5D4EK
 
-config SYS_CPU
-	default "armv7"
-
 config SYS_BOARD
 	default "sama5d4ek"
 
diff --git a/board/nvidia/nyan-big/Kconfig b/board/nvidia/nyan-big/Kconfig
index 6c42bb9..341c8d7 100644
--- a/board/nvidia/nyan-big/Kconfig
+++ b/board/nvidia/nyan-big/Kconfig
@@ -1,24 +1,12 @@
 if TARGET_NYAN_BIG
 
-config SYS_CPU
-	string
-	default "arm720t" if SPL_BUILD
-	default "armv7" if !SPL_BUILD
-
 config SYS_BOARD
-	string
 	default "nyan-big"
 
 config SYS_VENDOR
-	string
 	default "nvidia"
 
-config SYS_SOC
-	string
-	default "tegra124"
-
 config SYS_CONFIG_NAME
-	string
 	default "nyan-big"
 
 endif
diff --git a/board/samsung/smdk5420/Kconfig b/board/samsung/smdk5420/Kconfig
index ff28b1d..a9d62ff 100644
--- a/board/samsung/smdk5420/Kconfig
+++ b/board/samsung/smdk5420/Kconfig
@@ -14,15 +14,12 @@
 if TARGET_PEACH_PI
 
 config SYS_BOARD
-	string
 	default "smdk5420"
 
 config SYS_VENDOR
-	string
 	default "samsung"
 
 config SYS_CONFIG_NAME
-	string
 	default "peach-pi"
 
 endif
diff --git a/board/st/stv0991/Kconfig b/board/st/stv0991/Kconfig
index 8bda349..007712f 100644
--- a/board/st/stv0991/Kconfig
+++ b/board/st/stv0991/Kconfig
@@ -1,23 +1,15 @@
 if TARGET_STV0991
 
-config SYS_CPU
-	string
-	default "armv7"
-
 config SYS_BOARD
-	string
 	default "stv0991"
 
 config SYS_VENDOR
-	string
 	default "st"
 
 config SYS_SOC
-	string
 	default "stv0991"
 
 config SYS_CONFIG_NAME
-	string
 	default "stv0991"
 
 endif
diff --git a/board/sunxi/Kconfig b/board/sunxi/Kconfig
index 246cd9a..5ae491d 100644
--- a/board/sunxi/Kconfig
+++ b/board/sunxi/Kconfig
@@ -33,7 +33,6 @@
 endchoice
 
 config SYS_CONFIG_NAME
-	string
 	default "sun4i" if MACH_SUN4I
 	default "sun5i" if MACH_SUN5I
 	default "sun6i" if MACH_SUN6I