Make gcc-4.9 the default compiler (except on s390*)

git-svn-id: svn://svn.debian.org/svn/kernel/dists/trunk@22067 510b9475-24dd-0310-9b6c-e0eefe99d49f
[x86] Update linux-headers-* dependency on linux-compiler-*-x86

git-svn-id: svn://svn.debian.org/svn/kernel/dists/trunk@22068 510b9475-24dd-0310-9b6c-e0eefe99d49f
[arm*] Update linux-headers-* dependency on linux-compiler-*-arm

git-svn-id: svn://svn.debian.org/svn/kernel/dists/trunk@22069 510b9475-24dd-0310-9b6c-e0eefe99d49f
Delete unused compiler relations

git-svn-id: svn://svn.debian.org/svn/kernel/dists/trunk@22070 510b9475-24dd-0310-9b6c-e0eefe99d49f
List all the architectures not using gcc-4.9

git-svn-id: svn://svn.debian.org/svn/kernel/dists/trunk@22071 510b9475-24dd-0310-9b6c-e0eefe99d49f