kconfig: move some CONFIG_SYS_TEXT_BASE to Kconfig

We are moving various config options to Kconfig.  One of our next
targets is CONFIG_SYS_TEXT_BASE.

Historically, TEXT_BASE used to be defined in makefiles (config.mk)
and renamed to CONFIG_SYS_TEXT_BASE.

New boards define it in their header files (include/configs/<board>.h),
whereas some old boards still have it in their config.mk.

This commit moves CONFIG_SYS_TEXT_BASE from config.mk to Kconfig.
Eventually we can remove many board-specific config.mk.

Moving CONFIG_SYS_TEXT_BASE in C header files will be followed-up lator.

To avoid conflicts between Kconfig and board header files, a temporary
option CONFIG_TEXT_BASE_IN_KCONFIG needs to be introduced; it will be
removed after all the definitions of CONFIG_SYS_TEXT_BASE are moved to
Kconfig.

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

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
kbuild: remove CONFIG_SYS_TEXT_BASE handling from top Makefile

This code has been here to pass CONFIG_SYS_TEXT_BASE defined
in config.mk to C source code.

Since all the definitions in config.mk were removed in the previous
commit, let's remove unnecessary lines.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
kbuild: descend into drivers/ for SPL build

This patch allows the SPL build to descend into scripts/
(but no lines in drivers/Makefile are parsed for SPL for now).

This patch actually has no impact.  It is just the preparation
of upcoming refactoring.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
kconfig: move CONFIG_BOOTM_LINUX to Kconfig

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

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
BOOTM_LINUX
moveconfig: add dryrun option