New-line terminate error message that missed this convention

That could confuse library users that set their own error handler,
because there are already cases in libxslt that push a single message
in chunks (the same way as libxml2 does) and the user may be interested
in performing the message reconstruction on its own.

libxslt/numbers.c

@@ -222,7 +222,7 @@ xsltNumberFormatDecimal(xmlBufferPtr buffer,
     }
     if (i < 0)
         xsltGenericError(xsltGenericErrorContext,
-		"xsltNumberFormatDecimal: Internal buffer size exceeded");
+		"xsltNumberFormatDecimal: Internal buffer size exceeded\n");
     xmlBufferCat(buffer, pointer);
 }