The exec_target binary could segfault calling _exit(2) because r13
is not set up properly (and libc looks at that when performing a
syscall). Call SYS_exit using syscall(2) which doesn't seem to
have this problem.
Signed-off-by: NNicholas Piggin <npiggin@gmail.com>
Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>