sccvn: Correct the index of bias for IFN_LEN_STORE [PR110744]

sccvn: Correct the index of bias for IFN_LEN_STORE [PR110744]

Commit r14-2267-gb8806f6ffbe72e adjusts the arguments order
of LEN_STORE from {len,vector,bias} to {len,bias,vector},
in order to make them consistent with LEN_MASK_STORE and
MASK_STORE.  But it missed to update the related handlings
in tree-ssa-sccvn.cc, it caused the failure shown in PR
110744.  This patch is to fix the related handlings with
the correct index.

	PR tree-optimization/110744

gcc/ChangeLog:

	* tree-ssa-sccvn.cc (vn_reference_lookup_3): Correct the index of bias
	operand for ifn IFN_LEN_STORE.