kconfig: turn a python script to a shell script

Commit 51148790 added scripts/multiconfig.py written in Python 2
to adjust Kconfig for U-Boot.

The problem is that Python 2 and Python 3 are not compatible
with each other and some users are using Python 3.

We do not like to add host tool dependency for a basic build.

The script was complicated for a shell script and the code
may get unreadable but it is worthwhile.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Suggested-by: Igor Grinberg <grinberg@compulab.co.il>
add more comments to multiconfig.sh
kconfig: move
cosmetic: Kconfig: fix a typo

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
kconfig: add CONFIG_CROSS_COMPILE

Copy from Linux Kernel (with a few adjustments in comments).
tools: move_config
scripts/Lindent: import from Linux 3.16

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
tools/genboardscfg.py: Do not output SPLCPU field

Prior to Kconfig, the CPU field of boards.cfg could optionally have
":SPLCPU", like "armv7:arm720t".
(Actually this syntax was only used for Tegra platform.)

Now it is not necessary at all because CPU is defined by
CONFIG_SYS_CPU in Kconfig.

For Tegra platform, the Kconfig option is described as follows:

  config SYS_CPU
          string
          default "arm720t" if SPL_BUILD
          default "armv7" if !SPL_BUILD

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Series-cc: sjg
tools: moveconfig.py
tools/genboardscfg.py: facilitate adding new options

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Check if the boards.cfg is up-to-date

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>