BUG: perf error on syscalls for powerpc64.

Hi All,

1028ccf5 did a change for sys_call_table from a pointer to an array of
unsigned long, I think it's not proper, here is my reason:

sys_call_table defined as a label in assembler should be pointer array
rather than an array as described in 1028ccf5. If we defined it as an
array, then arch_syscall_addr will return the address of sys_call_table[],
actually the content of sys_call_table[] is demanded by arch_syscall_addr.
so 'perf list' will ignore all syscalls since find_syscall_meta will
return null
in init_ftrace_syscalls because of the wrong arch_syscall_addr.

Did I miss something, or Gcc compiler has done something newer ?

Cheers,
Zumeng