There are 3 families of Synopsys DeisgnWare ARC processors:
ARCompact/ARCv1 (32-bit), ARCv2 (32-bit) and ARCv3 (32-bit
and 64-bit targets). Upstream Newlib supports only ARCv1/2.
This commit prepares ARCv1/2 libgloss port to be reused by
ARCv3 port (except crt* files). Note that __ARC64__ macro
stands for all ARCv3 targets.
Signed-off-by: Yuriy Kolerov <ykolerov@synopsys.com>