kate: convert isn't a built in function

I have no idea how that got in there.

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/1240046

misc/kate/go.xml

@@ -66,7 +66,6 @@
       <item> close </item>
       <item> closed </item>
       <item> cmplx </item>
-      <item> convert </item>
       <item> copy </item>
       <item> imag </item>
       <item> len </item>