libosip2 appears to have support for the "ARC standard" (Advanced
RISC Computing), which is unrelated to Synopsys DesignWare ARC
processors. The check for this involves verifying the existence of
the "__arc__" macro. Unfortunately, this macro is also present
as a predefined built-in for the ARC processors, resulting into
build failures.
[Peter: add short comment in .mk files as well]
Signed-off-by: Mischa Jonker <mjonker@synopsys.com>
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>