powerpc remote target registers

[Andrew Cagney]

> But then the registers aren't marked as cached at all, so they're now requested from the target each time you do "info all-registers", even though they come up with 0s. Should I pretend the registers not supplied by the target were 0, or should I mark them as unavailable (i.e. the same as what having an "x" does) so at least it's consistent?

Ah, they should be supplied but with a value of zero.  The protocol (for 
  historic reasons) specifies that a short G packet should have the 
missing entries treated as zero (like you intended).

Andrew