tegra: kconfig: move board select menu and common settings

Becuase the board select menu in arch/arm/Kconfig is too big,
move the Tegra board select menu to tegra/Kconfig.

Insert the Tegra SoC select menu between the arch select and the
board select.

 Architecture select
 |-- Tegra Platform (Tegra)
     |- Tegra SoC select (Tegra20 / 30 / 114 / 124)
        |- Board select

Consolidate also common settings (CONFIG_SYS_CPU="armv7" and
CONFIG_SYS_SOC="tegra*") and always "select" CONFIG_SPL as follows:

  config TEGRA
          bool
          select SPL

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Cc: Tom Warren <twarren@nvidia.com>

configs/trimslice_defconfig

-CONFIG_SPL=y
 +S:CONFIG_ARM=y
++S:CONFIG_TEGRA=y
++S:CONFIG_TEGRA20=y
 +S:CONFIG_TARGET_TRIMSLICE=y

configs/venice2_defconfig

-CONFIG_SPL=y
 +S:CONFIG_ARM=y
++S:CONFIG_TEGRA=y
++S:CONFIG_TEGRA124=y
 +S:CONFIG_TARGET_VENICE2=y

configs/ventana_defconfig

-CONFIG_SPL=y
 +S:CONFIG_ARM=y
++S:CONFIG_TEGRA=y
++S:CONFIG_TEGRA20=y
 +S:CONFIG_TARGET_VENTANA=y

configs/whistler_defconfig

-CONFIG_SPL=y
 +S:CONFIG_ARM=y
++S:CONFIG_TEGRA=y
++S:CONFIG_TEGRA20=y
 +S:CONFIG_TARGET_WHISTLER=y

include/configs/tegra-common.h

@@ -14,7 +14,6 @@
  * High Level Configuration Options
  */
 #define CONFIG_ARMCORTEXA9		/* This is an ARM V7 CPU core */
-#define CONFIG_TEGRA			/* which is a Tegra generic machine */
 #define CONFIG_SYS_L2CACHE_OFF		/* No L2 cache */
 
 #include <asm/arch/tegra.h>		/* get chip and board defs */