[Buildroot] Update of Buildroot toolchains in the autobuilders

[Thomas Petazzoni]

Hello,

For your information, the pre-built Buildroot toolchains in the
autobuilders have seen some changes:

 * They have all been rebuilt with Buildroot 2015.11-rc1-71-g90d1299.
   This means that uClibc-ng 1.0.9 is used for the uClibc based
   toolchains.

 * Since mips64/uclibc support has been enabled, the br-mips64-n64-full
   toolchain is now uClibc-ng based instead of glibc based.

 * As requested by Vicente, two new toolchains have been added:
   mips32r6 and mips64r6-n64 (both little endian, hard float).

Best regards,

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com