split-path: Small fix for poor_ifcvt_pred (tsvc s258) [PR118505]

After r15-3436-gb2b20b277988ab, poor_ifcvt_pred returns false for
the case where the statement could trap but in this case trapping
instructions cannot be made unconditional so it is a poor ifcvt.

This fixes a small preformance regression with TSVC s258 at
`-O3 -ftrapping-math` on aarch64 where ifcvt would not happen
and we would still have a branch.

On a specific aarch64, we go from 0.145s down to 0.118s.

Bootstrapped and tested on x86_64-linux-gnu.

gcc/ChangeLog:

	PR tree-optimization/118505
	* gimple-ssa-split-paths.cc (poor_ifcvt_pred): Return
	true for trapping statements.

Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>