Prevent compiler warnings and potential OLC setting string truncation.

- Prevented compiler warnings when using
’-Wtautological-pointer-compare’ on development system (Darwin)
- Prevented possible string truncation when adding a newline to an OLC
setting string.

src/genolc.c

@@ -86,7 +86,7 @@ char *str_udupnl(const char *txt)
   ptr = (txt && *txt) ? txt : undef;
   CREATE(str, char, strlen(ptr) + 3);
 
-  strlcpy(str, ptr, strlen(ptr));
+  strlcpy(str, ptr, strlen(str));
   strcat(str, "\r\n");
 
   return str;