Remove unnecessary local variables

I found an unused local variables in a couple of places in the Python
code; this removes them.

gdb/ChangeLog
2017-02-10  Tom Tromey  <tom@tromey.com>

	* python/py-value.c (valpy_richcompare_throw): Remove unnecessary
	"cleanup" local.
	* python/py-type.c (typy_legacy_template_argument): Remove
	unnecessary "cleanup" local.