Less deps: Stop using old version of libsecp256k1 (#9947)

(Moving further to 0.7 would require upgrading rand first)

substrate/Cargo.lock

@@ -2623,17 +2623,6 @@ dependencies = [
  "digest 0.9.0",
 ]
 
-[[package]]
-name = "hmac-drbg"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c6e570451493f10f6581b48cdd530413b63ea9e780f544bfd3bdcaa0d89d1a7b"
-dependencies = [
- "digest 0.8.1",
- "generic-array 0.12.4",
- "hmac 0.7.1",
-]
-
 [[package]]
 name = "hmac-drbg"
 version = "0.3.0"
@@ -3787,22 +3776,6 @@ dependencies = [
  "libc",
 ]
 
-[[package]]
-name = "libsecp256k1"
-version = "0.3.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1fc1e2c808481a63dc6da2074752fdd4336a3c8fcc68b83db6f1fd5224ae7962"
-dependencies = [
- "arrayref",
- "crunchy",
- "digest 0.8.1",
- "hmac-drbg 0.2.0",
- "rand 0.7.3",
- "sha2 0.8.2",
- "subtle 2.4.0",
- "typenum",
-]
-
 [[package]]
 name = "libsecp256k1"
 version = "0.5.0"
@@ -3812,7 +3785,7 @@ dependencies = [
  "arrayref",
  "base64 0.12.3",
  "digest 0.9.0",
- "hmac-drbg 0.3.0",
+ "hmac-drbg",
  "libsecp256k1-core 0.2.2",
  "libsecp256k1-gen-ecmult 0.2.1",
  "libsecp256k1-gen-genmult 0.2.1",
@@ -3831,7 +3804,7 @@ dependencies = [
  "arrayref",
  "base64 0.12.3",
  "digest 0.9.0",
- "hmac-drbg 0.3.0",
+ "hmac-drbg",
  "libsecp256k1-core 0.2.2",
  "libsecp256k1-gen-ecmult 0.2.1",
  "libsecp256k1-gen-genmult 0.2.1",
@@ -5306,7 +5279,7 @@ dependencies = [
  "frame-support",
  "frame-system",
  "hex-literal",
- "libsecp256k1 0.3.5",
+ "libsecp256k1 0.6.0",
  "log 0.4.14",
  "pallet-balances",
  "pallet-contracts-primitives",