objsz: Don't call replace_uses_by on SSA_NAME_OCCURS_IN_ABNORMAL_PHI [PR94423]
The following testcase ICEs because the objsz pass calls replace_uses_by
on SSA_NAME_OCCURS_IN_ABNORMAL_PHI SSA_NAME. The following patch instead
of that calls replace_call_with_value, which will turn it into
xyz_123(ab) = 234;