register_get_last_cache_p() function

Free all memory allocated for EmbeddedICE register cache

@file Holds utilities to work with register caches. OpenOCD uses machine registers internally, and exposes them by name to Tcl scripts. Sets of related registers are grouped into caches. For example, a CPU core will expose a set of registers, and there may be separate registers associated with debug or trace modules.

Marks the contents of the register cache as invalid (and clean).

Private implementation of register_get_by_name() for ARC that doesn't skip not [yet] existing registers. Used in many places for iteration through registers and even for marking required registers as existing.