chore: minor code clean up · ch32-rs/ch58x-hal@e98a051

Build: examples/hardfault.rs#L32

failed to resolve: could not find `interrupt` in `qingke_rt`

Build: examples/hardfault.rs#L42

failed to resolve: could not find `interrupt` in `qingke_rt`

Build: examples/adc_temp.rs#L62

expected function, found `Adc<'_, ch58x_hal::peripherals::ADC>`

Build: examples/adc_temp.rs#L67

expected function, found `Adc<'_, ch58x_hal::peripherals::ADC>`

Build: examples/hardfault.rs#L92

field `ienr1` of struct `ch58x_hal::pac::pfic::RegisterBlock` is private

Process completed with exit code 101.

Build: src/ble/mod.rs#L12

unused import: `println`

Build: src/ble/gatt.rs#L4

unused import: `core::ptr`

Build: src/interrupt.rs#L1

unused imports: `Ordering`, `compiler_fence`

Build: src/interrupt.rs#L6

unused import: `crate::pac::__EXTERNAL_INTERRUPTS as _`

Build: src/interrupt.rs#L177

constant `PRIO_MASK` is never used

Build: src/ble/ffi.rs#L230