Only create the state dir if asked for a restartable build:
- introduce the config dir, where components can store their config files
- move the munged uClibc config file to the config dir
- now, the state dir really is an indication that a build can be restarted

Thanks to Groleo Marius <groleo@gmail.com> for spotting the inconsistency
of the state dir usage, and suggesting this change.

/trunk/scripts/build/libc/uClibc.sh | 6 3 3 0 +++---
/trunk/scripts/crosstool-NG.sh.in | 9 7 2 0 +++++++--
/trunk/scripts/functions | 15 12 3 0 ++++++++++++---
3 files changed, 22 insertions(+), 8 deletions(-)

# ARM specific configuration file

config ARCH_arm

    select ARCH_SUPPORTS_BOTH_ENDIAN

    select ARCH_DEFAULT_LE

    select ARCH_SUPPORT_ARCH

    select ARCH_SUPPORT_CPU

    select ARCH_SUPPORT_TUNE

    select ARCH_SUPPORT_FPU

    help

      The ARM architecture, as defined by:

        http://www.arm.com/

config ARCH_ARM_EABI

    bool

    prompt "Use EABI"

    default n

    help

      Set up the toolchain so that it generates EABI-compliant binaries.

config ARCH_ARM_ABI_OK

    bool

    default y

    depends on ! ARCH_ARM_EABI

    select ARCH_SUPPORT_ABI