SF patch 493739 2 Bugfixes for 2.2c1 (RISC OS specific), from

SF patch 493739 2 Bugfixes for 2.2c1 (RISC OS specific), from
Dietmar Schwertberger.
Bugfix candidate.
"""
RISCOS/Modules/getpath_riscos.c:
Include trailing '\0' when using strncpy [copy
strlen(...)+1 characters].

Lib/plat-riscos/riscospath.py:
Use riscosmodule.expand for os.path.abspath.
[fixes problems with site.py where
abspath("<Python$Dir>") returned
join(os.getcwd(), "<Python$Dir>") as e.g.
"SCSI::SCSI4.$.<Python$Dir>" because "<Python$Dir>"
wasn't recognised as an absolute path.]
"""