incorporate review feedback

Author: Felix Nieuwenhuizen

doc/interfaces/etas.rst

@@ -4,7 +4,7 @@ ETAS
 This interface adds support for CAN interfaces by `ETAS`_.
 The ETAS BOA_ (Basic Open API) is used.
 Install the "ETAS ECU and Bus Interfaces – Distribution Package".
-Only Windows is supported.
+Only Windows is supported by this interface. The Linux kernel v5.13 (and greater) natively supports ETAS ES581.4, ES582.1 and ES584.1 USB modules. To use these under Linux, please refer to :ref:socketcan.
 
 Bus
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