arc: gcc: Go from 4.4.7 to 4.8 for ARC

This fixes multiple issues, including:
 - 'operand out of range' errors (due to defaulting to
   medium calls instead of short calls)
 - library dependencies that were not being found

Signed-off-by: Mischa Jonker <mjonker@synopsys.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>