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(-)

# Compute x86_64-specific values

CT_DoArchTupleValues() {

    # The architecture part of the tuple:

    CT_TARGET_ARCH="${CT_ARCH}"

}