Remove xfail from gcc.dg/tree-ssa/20040204-1.c

So the xfail was there because at one point the difference
from having logical-op-non-short-circuit set to 1 or 0 made a
difference in being able to optimizing a conditional way.
This has not been true for over 10 years in this case so
instead of keeping on adding to the xfail list, removing it
is the right thing to do.

Committed as obvious after a test on x86_64-linux-gnu.

gcc/testsuite/ChangeLog:

	* gcc.dg/tree-ssa/20040204-1.c: Remove xfail.