updates: Add a seprated library towards devices API level above 21 to unwind call stack. Reason below:
For some devices of ARM arch, in which the system native libraries not contain exidx section to unwind call stack. In order to use eh_frame when exidx section not exist , we need 'dl_iterate_phdr' to find out the eh_frame section, this is a system api on ARM and only exist after api level 21.