ports: Auto-enable USB Network (NCM) when LWIP is enabled.

Automatically enable MICROPY_HW_NETWORK_USBNET when MICROPY_PY_LWIP
is enabled, following the same pattern as WEBSOCKET and WEBREPL.

This makes USB networking available by default on boards that support
both USB device mode and LWIP networking, while still allowing boards
to explicitly disable it by setting MICROPY_HW_NETWORK_USBNET=0.

Affects: STM32, RP2, MIMXRT, and Renesas-RA ports.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>
Signed-off-by: Andrew Leech <[email protected]>

Author: pi-anl

ports/mimxrt/mpconfigport.h

@@ -145,6 +145,9 @@ uint32_t trng_random_u32(void);
 #define MICROPY_PY_WEBSOCKET                (MICROPY_PY_LWIP)
 #define MICROPY_PY_WEBREPL                  (MICROPY_PY_LWIP)
 #define MICROPY_PY_LWIP_SOCK_RAW            (MICROPY_PY_LWIP)
+#ifndef MICROPY_HW_NETWORK_USBNET
+#define MICROPY_HW_NETWORK_USBNET           (MICROPY_PY_LWIP)
+#endif
 #ifndef MICROPY_PY_NETWORK_PPP_LWIP
 #define MICROPY_PY_NETWORK_PPP_LWIP         (MICROPY_PY_LWIP)
 #endif

ports/renesas-ra/mpconfigport.h

@@ -128,6 +128,9 @@
 #define MICROPY_PY_TIME_TIME_TIME_NS (1)
 #define MICROPY_PY_TIME_INCLUDEFILE "ports/renesas-ra/modtime.c"
 #define MICROPY_PY_LWIP_SOCK_RAW    (MICROPY_PY_LWIP)
+#ifndef MICROPY_HW_NETWORK_USBNET
+#define MICROPY_HW_NETWORK_USBNET   (MICROPY_PY_LWIP)
+#endif
 #ifndef MICROPY_PY_MACHINE
 #define MICROPY_PY_MACHINE          (1)
 #define MICROPY_PY_MACHINE_INCLUDEFILE "ports/renesas-ra/modmachine.c"

ports/rp2/mpconfigport.h

@@ -200,6 +200,9 @@
 #define MICROPY_SSL_MBEDTLS                     (1)
 #define MICROPY_PY_LWIP_PPP                     (MICROPY_PY_NETWORK_PPP_LWIP)
 #define MICROPY_PY_LWIP_SOCK_RAW                (MICROPY_PY_LWIP)
+#ifndef MICROPY_HW_NETWORK_USBNET
+#define MICROPY_HW_NETWORK_USBNET               (MICROPY_PY_LWIP)
+#endif
 
 // Hardware timer alarm index. Available range 0-3.
 // Number 3 is currently used by pico-sdk alarm pool (PICO_TIME_DEFAULT_ALARM_POOL_HARDWARE_ALARM_NUM)

ports/stm32/mpconfigport.h

@@ -152,6 +152,9 @@
 #define MICROPY_HW_SOFTSPI_MAX_BAUDRATE (HAL_RCC_GetSysClockFreq() / 48)
 #define MICROPY_PY_WEBSOCKET        (MICROPY_PY_LWIP)
 #define MICROPY_PY_WEBREPL          (MICROPY_PY_LWIP)
+#ifndef MICROPY_HW_NETWORK_USBNET
+#define MICROPY_HW_NETWORK_USBNET   (MICROPY_PY_LWIP)
+#endif
 #ifndef MICROPY_PY_NETWORK
 #define MICROPY_PY_NETWORK          (1)
 #endif