rust: kernel: fix non-empty lines after section headers

Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Author: ojeda

rust/kernel/build_assert.rs

@@ -9,6 +9,7 @@
 /// be called, a build error will be triggered.
 ///
 /// # Examples
+///
 /// ```
 /// # use kernel::build_error;
 /// #[inline]

rust/kernel/fs/param.rs

@@ -434,6 +434,7 @@ macro_rules! count_brace_items {
 /// Defines the file system parameters of a given file system context.
 ///
 /// # Examples
+///
 /// ```
 /// # use kernel::prelude::*;
 /// # use kernel::{c_str, fs, str::CString};

rust/kernel/module_param.rs

@@ -211,6 +211,7 @@ macro_rules! impl_module_param {
 /// Generate a static [`kernel_param_ops`](../../../include/linux/moduleparam.h) struct.
 ///
 /// # Examples
+///
 /// ```ignore
 /// make_param_ops!(
 ///     /// Documentation for new param ops.