Add fsabs, fdabs, fsneg, fdneg, fsmove and fdmove.
The value is converted using the new floatx80_round() function.
Backports commit 77bdb2292492fafc4bc0fbb4d8c44fdd0ef1fa8e from qemu
fmovecr moves a floating point constant from the
FPU ROM to a floating point register.
Backports commit 9d403660d91229922c2786e81c23cc9dd8e644f1 from qemu
Coldfire uses float64, but 680x0 use floatx80.
This patch introduces the use of floatx80 internally
and enables 680x0 80bits FPU.
Backports commit f83311e4764f1f25a8abdec2b32c64483be1759b from qemu