[binutils-gdb] x86: x87-related adjustments

[sergiodj+buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT 0e0eea782025d92f894f6d132aae2507c6a90a7b ***

Author: Jan Beulich <jbeulich@novell.com>
Branch: master
Commit: 0e0eea782025d92f894f6d132aae2507c6a90a7b

x86: x87-related adjustments

Neither 287 wrt 8087 nor 387 wrt 287 are proper supersets - in each case
some insns get removed from the ISA (they become NOPs, but code intended
for newer co-processors should not use them).

Furthermore with .no87, ST should not be recognized as a register name.