chore: Remove 4.14 related io_uring checks

io_uring is not supported on 4.14 hosts. Since #4689 dropped
support for 4.14 hosts, and 5.10 does support io_uring, remove various
checks related to unsupported (4.14) host kernels.

Also update some of our unittests to always test both the sync and async
block engines. Previously, we only tested the sync engine on 4.14 hosts,
and only the async engien on 5.10 hosts. With the removal of 4.14 hosts,
this meant that we were no longer unittesting the sync engine in these
tests at all. Thus, have all the tests unconditionally test both
engines.

Signed-off-by: Patrick Roy <[email protected]>

Author: roypat

src/utils/src/kernel_version.rs

@@ -85,28 +85,6 @@ impl std::fmt::Display for KernelVersion {
     }
 }
 
-pub fn min_kernel_version_for_io_uring() -> KernelVersion {
-    KernelVersion::new(5, 10, 51)
-}
-
-#[macro_export]
-macro_rules! skip_if_io_uring_unsupported {
-    () => {
-        if KernelVersion::get().unwrap() < min_kernel_version_for_io_uring() {
-            return;
-        }
-    };
-}
-
-#[macro_export]
-macro_rules! skip_if_io_uring_supported {
-    () => {
-        if KernelVersion::get().unwrap() >= min_kernel_version_for_io_uring() {
-            return;
-        }
-    };
-}
-
 #[cfg(test)]
 mod tests {
     use super::*;