stm32/sdram: Fix compile issue from unused sdram startup test flag.
@@ -501,6 +501,7 @@ void stm32_main(uint32_t reset_mode) {
#if MICROPY_HW_SDRAM_SIZE
sdram_init();
bool sdram_valid = true;
+ UNUSED(sdram_valid);
#if MICROPY_HW_SDRAM_STARTUP_TEST
sdram_valid = sdram_test(true);
#endif
