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(-)

# powerpc specific configuration file

# depends on EXPERIMENTAL

config ARCH_powerpc64

    select ARCH_64

    select ARCH_SUPPORT_ABI

    select ARCH_SUPPORT_CPU

    select ARCH_SUPPORT_TUNE

    help

      The PowerPC architecture, as defined by:

        http://www.ibm.com/developerworks/eserver/articles/archguide.html