(ia64_get_cached_proc_info): Rename from ia64_script_lookup() and modify it so
it directly updates the proc-info if the necessary script is in the cache.
(script_new): Remove locking comments and adjust formatting.
(ia64_find_save_locs): If global caching is enabled, mask signal delivery and
hold the cache lock while accessing the cache.
(ia64_script_cache_init): Initialize the cache lock.
(Logical change 1.59)