Cross Toolchain Updates for Quantal and GCC 4.7

[hrw 3rd May 2012] Would be great to have eglibc built with gcc-4.7 in Quantal first to be able to bootstrap cross compiler like we do today. Otherwise I will have to build gcc-4.6/cross to build eglibc and then build libgcc/4.7 at next step.
[hrw 14.05.2012] during UDS-Q I discussed with Matthias Klose about patches and sent them. As he is on vacations now we get back to them in June. In meantime I will keep them updated and used.
[hrw 15.05.2012] binutils split out of arm*-cross-toolchain-base and waits in NEW queue.
[hrw 19.05.2012] binutils landed in Ubuntu, dpkg-cross got fix, a-c-t-b got fixes and upload. gcc-linaro/4.7/cross fixed, pushed, recipe created.
[hrw 21.05.2012] gcc-4.7/cross uploaded into Ubuntu - waits in NEW queue. gcc-linaro-4.7/cross scheduled for build. gcc-linaro/cross built fine for amd64/i386, gcc-linaro/native fails on arm/i386 - will look at it when time allow.
[hrw 23.05.2012] gcc-4.7/cross landed in Ubuntu - will upload today with fixes for bug 1003226.

Meta:
Headline: Cross Toolchain updated at both Ubuntu Quantal (12.10) and Linaro GCC CI, based on GCC 4.7
Acceptance: Cross toolchain updated to 4.7. Packages at Quantal and CI updated to reflect the new packages.

Work items:
Update CI gcc-linaro native to 4.7: DONE
Create LP recipe for gcc-linaro native: DONE
Publish gcc-linaro native in PPA: DONE
Update CI gcc-linaro cross to 4.7 and armhf target: DONE
Create LP recipe for gcc-linaro cross: DONE
Publish gcc-linaro cross in PPA: DONE
Merge gcc and binutils changes from cross toolchain into ubuntu: POSTPONED
Create binutils/cross package: DONE
Adapt a-c-t-b to not ship binutils: DONE
Adapt a-c-t-b to build gcc-4.6 for eglibc and gcc-4.7 for libgcc: DONE
Upload binutils/a-c-t-b to Ubuntu: DONE
Check why libc6-dev-armhf-cross has /usr/TRIPLET/include/TRIPLET/bits directory: DONE
Upload dpkg-cross to Ubuntu: DONE
Create gcc-4.7/cross packages: DONE
Upload gcc-4.7/cross to Ubuntu: DONE