libafs: fix IOPEN for amd64 solaris

libafs: fix IOPEN for amd64 solaris

Solaris afs_syscall_iopen was returning the fd in r_val2 for 64-bit
architectures (for 5.7 and beyond). If we are little-endian, though,
we want the return value in r_val1; otherwise we just always return fd
0. So, put the fd in r_val1 if we are little-endian.

Change-Id: I8553c338625e9c50f846f4676b53ea8f054b7a73
Reviewed-on: http://gerrit.openafs.org/2457
Tested-by: Andrew Deason <adeason@sinenomine.net>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
Tested-by: Derrick Brashear <shadow@dementia.org>