sys_fhopen() returns success (error=0) without valid file descriptor when regular file vnode lacks VM object

Summary

In sys_fhopen after VOP_OPEN succeeds if vnode is VREG but vp->v_object==NULL code prints warning jumps to bad_drop without setting error code. bad_drop clears descriptor drops file falls through to bad/done returns error=0 success. sysmsg_result never set to valid fd so caller receives success but has no open file descriptor result register contains whatever syscall framework left (typically 0 stdin).