Rollup merge of #67966 - popzxc:core-std-matches, r=Centril

Use matches macro in libcore and libstd

This PR replaces matches like

```rust
match var {
    value => true,
    _ => false,
}
```

with use of `matches!` macro.

r? @Centril

1 files changed, 1 insertions, 4 deletions

diff --git a/src/libcore/task/poll.rs b/src/libcore/task/poll.rs
index d567ae54577..b3a4bd20b8f 100644
--- a/src/libcore/task/poll.rs
+++ b/src/libcore/task/poll.rs
@@ -39,10 +39,7 @@ impl<T> Poll<T> {
     #[inline]
     #[stable(feature = "futures_api", since = "1.36.0")]
     pub fn is_ready(&self) -> bool {
-        match *self {
-            Poll::Ready(_) => true,
-            Poll::Pending => false,
-        }
+        matches!(*self, Poll::Ready(_))
     }
 
     /// Returns `true` if this is `Poll::Pending`