Enable timg0 for clock calibration

Author: bugadani

esp-hal/src/clock/mod.rs

@@ -279,6 +279,9 @@ impl Clocks {
     ) -> (u32, Rate) {
         use esp_rom_sys::rom::ets_delay_us;
 
+        use crate::{peripherals::Peripherals, system::PeripheralGuard};
+        let _guard = PeripheralGuard::new(Peripherals::Timg0);
+
         #[cfg(timergroup_rc_fast_calibration_divider)]
         let calibration_divider = if rtc_clock == TimgCalibrationClockConfig::RcFastDivClk
             && crate::soc::chip_revision_above(property!(