Fix MIPS emulation by disabling GCC 4.8

A previous patch switched the standalone toolchain to use
GCC 4.8, instead of 4.6 on Linux. Unfortunately, this breaks
MIPS emulation (Jellybean system image does not boot), and it's
really difficult to understand why.

This patch reverts the Linux toolchain to 4.6, note that this only
affects standalone builds (not platform ones).

Change-Id: I4d4c1bf3fdcd38fd8dbaffcb618319560511962c
1 file changed