ethernet lib: add only zephyr architecture in library properties

Author: leonardocavagnis

libraries/Ethernet/library.properties

@@ -6,5 +6,5 @@ sentence=Enables network connection (local and Internet) using Ethernet on Zephy
 paragraph=With this library you can connect to Internet via Ethernet. The library provides both Client and server functionalities. The library permits you to connect to a local network also with DHCP and to resolve DNS.
 category=Communication
 url=http://www.arduino.cc/en/Reference/Ethernet
-architectures=zephyr,zephyr_portenta,zephyr_nicla,zephyr_giga
+architectures=zephyr
 includes=Ethernet.h