sp-std removal from substrate/primitives (#3274)

This PR removes sp-std crate from substrate/primitives sub-directories.

For now crates that have `pub use` of sp-std or export macros that would
necessitate users of the macros to `extern crate alloc` have been
excluded from this PR.

There should be no breaking changes in this PR.

---------

Co-authored-by: Koute <koute@users.noreply.github.com>

substrate/primitives/tracing/src/lib.rs

@@ -37,6 +37,8 @@
 
 #![cfg_attr(not(feature = "std"), no_std)]
 
+extern crate alloc;
+
 #[cfg(feature = "std")]
 use tracing;
 pub use tracing::{

substrate/primitives/tracing/src/types.rs

@@ -15,11 +15,11 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use alloc::{vec, vec::Vec};
 use codec::{Decode, Encode};
 /// Types for wasm based tracing. Loosly inspired by `tracing-core` but
 /// optimised for the specific use case.
 use core::{fmt::Debug, format_args};
-use sp_std::{vec, vec::Vec, Writer};
 
 /// The Tracing Level – the user can filter by this
 #[derive(Clone, Encode, Decode, Debug)]
@@ -132,9 +132,9 @@ impl From<bool> for WasmValue {
 
 impl From<core::fmt::Arguments<'_>> for WasmValue {
 	fn from(inp: core::fmt::Arguments<'_>) -> WasmValue {
-		let mut buf = Writer::default();
+		let mut buf = alloc::string::String::default();
 		core::fmt::write(&mut buf, inp).expect("Writing of arguments doesn't fail");
-		WasmValue::Formatted(buf.into_inner())
+		WasmValue::Formatted(buf.into_bytes())
 	}
 }