Add frame_support::crypto::ecdsa::Public.to_eth_address() (k256-based) and use it in pallets (#11087)

* `ecdsa::Public::to_eth_address` + test, beefy-mmr `convert()` to use it, contracts Ext interface

* `seal_ecdsa_to_eth_address` all but benchmark done

* `seal_ecdsa_to_eth_address` + wasm test

* `seal_ecdsa_to_eth_address` + benchmark

* fixed dependencies

* Apply suggestions from code review

Co-authored-by: Alexander Theißen <alex.theissen@me.com>

* fixes from review #1

* ecdsa::Public(*pk).to_eth_address() moved to frame_support and contracts to use it

* beefy-mmr to use newly added frame_support function for convertion

* a doc fix

* import fix

* benchmark fix-1 (still fails)

* benchmark fixed

* Apply suggestions from code review

Co-authored-by: Alexander Theißen <alex.theissen@me.com>

* fixes on Alex T feedback

* to_eth_address() put into extension trait for sp-core::ecdsa::Public

* Update frame/support/src/crypto/ecdsa.rs

Co-authored-by: Alexander Theißen <alex.theissen@me.com>

* Update frame/contracts/src/wasm/mod.rs

Co-authored-by: Alexander Theißen <alex.theissen@me.com>

* fixes on issues pointed out in review

* benchmark errors fixed

* fmt fix

* EcdsaRecoverFailed err docs updated

* Apply suggestions from code review

Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>

* make applied suggestions compile

* get rid of unwrap() in runtime

* Remove expect

Co-authored-by: Alexander Theißen <alex.theissen@me.com>
Co-authored-by: Bastian Köcher <bkchr@users.noreply.github.com>
Co-authored-by: Bastian Köcher <info@kchr.de>

substrate/frame/support/Cargo.toml

@@ -35,6 +35,7 @@ impl-trait-for-tuples = "0.2.2"
 smallvec = "1.8.0"
 log = { version = "0.4.14", default-features = false }
 sp-core-hashing-proc-macro = { version = "5.0.0", path = "../../primitives/core/hashing/proc-macro" }
+k256 = { version = "0.10.2", default-features = false, features = ["ecdsa"] }
 
 [dev-dependencies]
 assert_matches = "1.3.0"