arm: use PTRACE_GETVFPREGS instead of GETFPREGS

If enabled CONFIG_VFP, we should use PTRACE_GETVFPREGS instead of GETFPREGS.
Most of arm hardwares(since then armv6) use VFP. If we need runtime checking of
vfp, we should parse /proc/cpu_info or use any other techniques.

Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Signed-off-by: Myungjoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>