fix cgcc ELF version for ppc64/pcc64le

fix cgcc ELF version for ppc64/pcc64le

Commit e0306fe0 "cgcc: teach cgcc about ppc64[le]" add support
for PPC64 to cgcc by adding the needed options like '-m64' &
'-m{little,big}-endian' and defines likes '-D__PPC64__=1'.

In this commit the defined '-D_CALL_ELF=2' was also added
but the value of 2 is for ELF v2 ABI, normally used for ppc64le,
while the older ELF ABI, normally used for plain ppc64 should use
'-D_CALL_ELF=2'.

Fix this by using the value of 1 or 2 for '_CALL_ELF' depending
if the architecture is ppc64 or ppc64le.

Fixes: e0306fe0b725af6e2e7ff59d7f0d99c96315791a
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Tested-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Signed-off-by: Christopher Li <sparse@chrisli.org>