lseek64 is not required by linux

I have tested this on 64 bit linux system with following uname info
 3.2.0-29-generic #46-Ubuntu SMP Fri Jul 27 17:03:23 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

32 bit system have following uname - a info
Linux daku_daddy 3.7.10-1.32-pae #1 SMP Thu May 8 00:09:34 UTC 2014 (5978d00) i686 i686 i386 GNU/Linux

I have not tested on windows since i have not touched the windows macro part. so i assume my commit  should not interfere with windows.

this patch compel code to use lseek instead of lseek64, since according to manual its done internally.