boards: xtensa: olimex_esp32_evb: list TWAI as supported

List the Two-Wire Automotive Interface (TWAI) as supported in the Olimex
ESP32-EVB board documentation.

Signed-off-by: Henrik Brix Andersen <hebad@vestas.com>

Author: henrikbrixandersen

boards/xtensa/olimex_esp32_evb/doc/index.rst

@@ -75,6 +75,8 @@ features:
 +-----------+------------+-------------------------------------+
 | TRNG      | on-chip    | entropy                             |
 +-----------+------------+-------------------------------------+
+| TWAI      | on-chip    | CAN controller                      |
++-----------+------------+-------------------------------------+
 | UART      | on-chip    | uart                                |
 +-----------+------------+-------------------------------------+
 | WDT       | on-chip    | watchdog                            |