* Makefile.in (s390-tdep.o): Add dependency on $(prologue_value_h).

	* Makefile.in (s390-tdep.o): Add dependency on $(prologue_value_h).
	* s390-tdep.c: Include "prologue-value.h".
	(struct prologue_value): Remove.
	(pv_set_to_unknown, pv_set_to_constant, pv_set_to_register,
	pv_constant_last, pv_add, pv_add_constant, pv_subtract,
	pv_logical_and, pv_is_identical, pv_is_register): Remove.
	(compute_x_addr): Remove, replace by ...
	(s390_addr): ... this new function.
	(struct s390_prologue_data): Use pv_t instead of prologue_value.
	(s390_store, s390_load): Likewise.
	(s390_prologue_frame_unwind_cache): Likewise.
	(s390_analyze_prologue): Likewise.  Also, simplify and combine
	several conditional statements.