Change PUCHAR to PCHAR.

Change PUCHAR to PCHAR.
(PTR_TO_OFFSET): Cast ptr to unsigned char *.
(relocate_offset):
(get_section_info):
(copy_executable_and_dump_data): Remove unnecessary static defs.
(copy_executable_and_dump_data): Fix compile warnings.
(unexec): Ignore old_name, and use the actual location
of the current executable instead.  Base new_name on this.