use get_clock() instead of hard code freq for baud rate calc

imxrt-hal/src/can/mod.rs

@@ -326,7 +326,7 @@ where
     }
 
     pub fn set_baud_rate(&mut self, baud: u32) {
-        let clock_freq = 24_000_000;
+        let clock_freq = self.get_clock();
 
         let mut divisor = 0;
         let mut best_divisor: u32 = 0;