target-ppc: Add VSX ISA2.06 Multiply Add Instructions

target-ppc: Add VSX ISA2.06 Multiply Add Instructions

This patch adds the VSX floating point multiply/add instructions
defined by V2.06 of the PowerPC ISA:

  - xsmaddadp,  xvmaddadp,  xvmaddasp
  - xsmaddmdp,  xvmaddmdp,  xvmaddmsp
  - xsmsubadp,  xvmsubadp,  xvmsubasp
  - xsmsubmdp,  xvmsubmdp,  xvmsubmsp
  - xsnmaddadp, xvnmaddadp, xvnmaddasp
  - xsnmaddmdp, xvnmaddmdp, xvnmaddmsp
  - xsnmsubadp, xvnmsubadp, xvnmsubasp
  - xsnmsubmdp, xvnmsubmdp, xvnmsubmsp

Signed-off-by: Tom Musta <tommusta@gmail.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Alexander Graf <agraf@suse.de>