support/config-fragments/autobuild: update toolchains for 2017.11-rc1

All Buildroot pre-built toolchains have been rebuilt with Buildroot
2017.11-rc1, so that they have the latest version of
glibc/musl/uClibc, and also the latest gcc/binutils updates.

Specifically, this will fix the build failures on Blackfin that were
due to the missing accept4() support:

  http://autobuild.buildroot.net/results/8b5a72dd7cde685f6f68f46aeee8b1b60c96d559/
  (openobex)

  http://autobuild.buildroot.net/results/b19dd9ed29944d7f79c6f824669e3baaa0bb045a/


  (libiio)

In terms of changes to the toolchains:

 - AArch64 glibc toolchain changed to use 4.4 kernel headers instead
   of 4.1, in order to increase the variety of kernel header versions
   being tested.

 - Most configurations now use 4.13 kernel headers instead of 4.12
   (except the configurations that were explicitly using an older
   kernel headers version)

 - The mips64 n64 configuration is changed from using gcc 4.9 to gcc
   5, since another ARM configuration already tests gcc 4.9.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>