iproute2: fixup CCOPTS to unbreak build

CCOPTS is also used for HOSTCC in the netem/ directory which contains
host tools so just ditch it there to avoid extra non-native
optimizations to sweep by.

Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>