Bug 25050: X87 FPU Special Purpose Registers

Summary:
  - For x86_64-FreeBSD Platform:
    -- LLDB now provides correct values of X87 FPU
       Special Purpose Registers like fstat, ftag, fctrl etc..

Signed-off-by: Abhishek Aggarwal <abhishek.a.aggarwal@intel.com>

Reviewers: emaste, mikesart, clayborg

Subscribers: emaste

Differential Revision: http://reviews.llvm.org/D13434

llvm-svn: 249379