fix(lp_io): allow edge wakeup types for LP-IO on chips which support it

examples/system/ulp/lp_core/gpio_wakeup/main/lp_core_gpio_wake_up_example_main.c

@@ -34,7 +34,7 @@ static void wakeup_gpio_init(void)
     rtc_gpio_set_direction(WAKEUP_PIN, RTC_GPIO_MODE_INPUT_ONLY);
     rtc_gpio_pulldown_dis(WAKEUP_PIN);
     rtc_gpio_pullup_en(WAKEUP_PIN);
-    rtc_gpio_wakeup_enable(WAKEUP_PIN, GPIO_INTR_LOW_LEVEL);
+    rtc_gpio_wakeup_enable(WAKEUP_PIN, GPIO_INTR_NEGEDGE);
 }
 
 void app_main(void)

examples/system/ulp/lp_core/gpio_wakeup/main/ulp/main.c

@@ -14,9 +14,6 @@ int main (void)
 {
     ulp_lp_core_wakeup_main_processor();
 
-    /* Wakeup interrupt is a level interrupt, wait 1 sec to
-        allow user to release button to avoid waking up the ULP multiple times */
-    ulp_lp_core_delay_us(1000*1000);
     ulp_lp_core_gpio_clear_intr_status();
 
     return 0;