* dwarf2-frame.h: Update copyright.
(enum dwarf2_frame_reg_rule): New.
(struct dwarf2_frame_state_reg): New.
(dwarf2_frame_sniffer, dwarf2_frame_base_sniffer): Make extern.
* dwarf2-frame.c: Update copyright.
(enum dwarf2_reg_rule): Remove.
(struct dwarf2_frame_state): Remove defenition of `struct
dwarf2_frame_state_reg'.
(read_reg): Call get_frame_arch to get the architecture instead of
using CURRENT_GDBARCH.
(execute_cfa_program): Prefix old `enum dwarf2_reg_rule' tags with
DWARF2_FRAME_.
(dwarf2_frame_init_reg): New function.
(dwarf2_frame_cache): Call get_frame_arch to get the architecture
instead of using CURRENT_GDBARCH. Call dwarf2_frame_init_reg to
initialize the register state. Prefix old `enum dwarf2_reg_rule'
tags with DWARF2_FRAME_.
(dwarf2_frame_prev_register): Call get_frame_arch to get the
architecture instead of using CURRENT_GDBARCH. Prefix old `enum
dwarf2_reg_rule' tags with DWARF2_FRAME_.