* gcc.c-torture/execute/ieee/ieee.exp: Skip if pdp11.
* gcc.c-torture/compile/20000804-1.c: Skip if pdp11 -O0.
* gcc.c-torture/compile/20020312-1.c: Ditto.
* gcc.c-torture/compile/20040101-1.c: Skip if pdp11 -O1, -O2, or
-Os.

From-SVN: r168370