Remove DLL properties which are not applicable for soft PHYs
since these PHYs do not have a DLL to enable.

Acked-by: Francesco Dolcini <francesco.dolcini@toradex.com> # Verdin AM62
Signed-off-by: Judith Mendez <jm@ti.com>
Tested-by: Wadim Egorov <w.egorov@phytec.de>
Link: https://lore.kernel.org/r/20240213235701.2438513-7-jm@ti.comSigned-off-by: Vignesh Raghavendra <vigneshr@ti.com>