off-by-one fix for py-linetable.c

off-by-one fix for py-linetable.c

While digging into a different memory corruption error, I happened to
notice one coming from the linetable code.  In a couple of spots, the
wrong termination condition was used in a loop, leading gdb to read
one element past the end of the linetable.

Built and regtested on x86-64 Fedora 18.  Also verified using
valgrind.  I'm checking this in.

2013-11-14  Tom Tromey  <tromey@redhat.com>

	* python/py-linetable.c (ltpy_has_line)
	(ltpy_get_all_source_lines): Fix loop termination condition.