arm: dts: k3-am65-main: Add itapdly and clkbuf-sel values

Add the appropriate itapdly and clkbuf-sel values required for
some lower speed modes.

Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>