Dateiendung gefixt.

Ist ein rst...

Change-Id: Icec464035891defed581691bbb89d18f007c4092
diff --git a/doc/sphinx/props/P_TELNET_CHARSET b/doc/sphinx/props/P_TELNET_CHARSET.rst
similarity index 100%
rename from doc/sphinx/props/P_TELNET_CHARSET
rename to doc/sphinx/props/P_TELNET_CHARSET.rst