frame: support for serde added (#14261)

* frame: support for serde added

- enabled `serde` features in dependent crates, no gate feature introduced, linker should do the job and strip unused code.

- frame::staking: added impl of `serde::Serialize, serde::Deserialize` for `enum Forcing`

- primitives::runtime: impl_opaque_keys macro provides `Serialize/Deserialize` impl if `serde` is enabled

- primitives::staking: added impl of `serde::Serialize`, `serde::Deserialize` for `enum StakerStatus`

* frame::support: serde for pallets' GenesisConfig enabled in no-std

* Cargo.lock updated

* Update primitives/staking/Cargo.toml

Co-authored-by: Bastian Köcher <git@kchr.de>

* fix

* Cargo.lock update + missed serde/std in beefy

---------

Co-authored-by: Bastian Köcher <git@kchr.de>

substrate/frame/support/Cargo.toml

@@ -13,7 +13,7 @@ readme = "README.md"
 targets = ["x86_64-unknown-linux-gnu"]
 
 [dependencies]
-serde = { version = "1.0.163", optional = true, features = ["derive"] }
+serde = { version = "1.0.163", default-features = false, features = ["alloc", "derive"] }
 codec = { package = "parity-scale-codec", version = "3.2.2", default-features = false, features = ["derive", "max-encoded-len"] }
 scale-info = { version = "2.5.0", default-features = false, features = ["derive"] }
 frame-metadata = { version = "15.1.0", default-features = false, features = ["v14", "v15-unstable"] }
@@ -54,7 +54,7 @@ std = [
 	"sp-core/std",
 	"k256/std",
 	"once_cell",
-	"serde",
+	"serde/std",
 	"sp-api/std",
 	"sp-io/std",
 	"codec/std",