[oe] RFC: SDK/external-toolchain fixes

[Denys Dmytriyenko]

Hi,

I've been playing with OE's SDK and external-toolchain features lately and
stumbled upon couple of issues. Thanks to Philip Balister for commiting
trivial fixes in, now I have 2 more, which require wider review. Please let
me know of any problems or comments. Thanks.


#1 gcc-cross-sdk 4.3.1 missing include-fixed
http://bugs.openembedded.net/show_bug.cgi?id=4536

gcc 4.3.x has some GCC-provided headers in include-fixed (namely limits.h),
which are missing in the gcc-cross-sdk version, rendering external toolchain
unusable.

Provided patch copies them in the include directory as a temporary solution.
A similar temporary solution is present in gcc-cross_4.3.1, see
do_stage_append()


#2 external-toolchain misses providing runtime libgcc
http://bugs.openembedded.net/show_bug.cgi?id=4542

Since external-toolchain misses specifying libgcc as provided runtime library,
dependency tree picks up either gcc-cross or even gcc-noemu...

Attached patch fixes the problem.


-- 
Denys