dts: added stm32f103Xd.dts file

This commit adds stm32f103xd series dts file that was missing.

Also, changed stm32f103xe.dts for highlighting the differences between
f103xd and f103xe series.

Signed-off-by: Deimantas Aukštkalnis <deimantas.aukstkalnis@teltonika.lt>