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(-)

 # Bare metal config options

 config KERNEL_bare_metal

     select BARE_METAL

     help

       'Bare metal' refers to those programs that run without any kernel.

       You probably want to say 'y' here if you plan to use your compiler

       to build bootloaders. It is not yet suitable to build Linux kernels,

       though, because the APCI stuff relies on the target C library headers

       being available?!?!...