[IA64] regset: 32-bit support

This is the 32-bit regset implementation under IA64. Basically register
read/write, which is derived from current ptrace register read/write.
This version added TLS support.

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>