update clock method name in octospi

Author: richardeoin

src/xspi/octospi.rs

@@ -530,10 +530,7 @@ macro_rules! octospi_impl {
                 // Disable OCTOSPI before configuring it.
                 regs.cr.write(|w| w.en().clear_bit());
 
-                let spi_kernel_ck = match Self::get_clock(clocks) {
-                    Some(freq_hz) => freq_hz.0,
-                    _ => panic!("OCTOSPI kernel clock not running!"),
-                };
+                let spi_kernel_ck = Self::kernel_clk_unwrap(clocks).0;
 
                 // Configure clock
                 let hyperbus: HyperbusConfig = hyperbus.into();