checked_math: use a panic

This reduces compute use further and still produces good error messages.

programs/mango-v4/src/util.rs

@@ -11,8 +11,7 @@ pub(crate) use zip;
 #[macro_export]
 macro_rules! checked_math {
     ($x: expr) => {
-        checked_math::checked_math!($x)
-            .ok_or_else(|| error!(crate::error::MangoError::MathError))?
+        checked_math::checked_math!($x).unwrap_or_else(|| panic!("math error"))
     };
 }
 pub(crate) use checked_math;