Heads up, deprecate read_pc(), read_fp()

[Andrew Cagney]

Just a heads up,  don't know when but hopefully soon these methods can 
be deprecated:

- they (like the rest of the old register cache code) rely on global state

- their behavior doesn't match their namesake:
-- read_pc() can return either PC or PC+DECR_PC_AFTER_BREAK or 
PC+DECR_PC_AFTER_HW_BREAK or ?
-- read_fp() returns an almost random pointer onto the stack.  A frame 
starts out with frame->frame = read_pc() but then INIT_FRAME_PC, 
INIT_FRAME_PC_FIRST, INIT_FRAME_EXTRA_INFO, INIT_FRAME_SAVED_REGS, or ? 
go and change it :-(

I think it is pretty clear that the replacement for both of these will take:

	- the register cache
	- the stop reason
	- a cache buffer to save any analysis data (so one can share with the 
other)

as parameters.

enjoy,
Andrew