literal-expr.md: say that suffixes are removed before interpreting numbers

Author: mattheww

src/expressions/literal-expr.md

@@ -96,6 +96,8 @@ The value of the expression is determined from the string representation of the
 
 * If the radix is not 10, the first two characters are removed from the string.
 
+* Any suffix is removed from the string.
+
 * Any underscores are removed from the string.
 
 * The string is converted to a `u128` value as if by [`u128::from_str_radix`] with the chosen radix.
@@ -136,6 +138,8 @@ let x: f64 = 2.; // type f64
 
 The value of the expression is determined from the string representation of the token as follows:
 
+* Any suffix is removed from the string.
+
 * Any underscores are removed from the string.
 
 * The string is converted to the expression's type as if by [`f32::from_str`] or [`f64::from_str`].