SPARC64: fp_disabled checks on ldfa/lddfa/ldqfa

ldfa/lddfa/ldqfa instructions should raise fp_disabled exceptions
if %pstate.PEF==0 or %fprs.FEF==0.

Signed-off-by: Tsuneo Saito <tsnsaito@gmail.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
