remove old dependency

Cargo.lock

@@ -50,15 +50,6 @@ version = "1.4.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "14c189c53d098945499cdfa7ecc63567cf3886b3332b312a5b4585d8d3a6a610"
 
-[[package]]
-name = "core2"
-version = "0.3.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "239fa3ae9b63c2dc74bd3fa852d4792b8b305ae64eeede946265b6af62f1fff3"
-dependencies = [
- "memchr",
-]
-
 [[package]]
 name = "cortex-m"
 version = "0.7.7"
@@ -233,12 +224,6 @@ dependencies = [
  "scopeguard",
 ]
 
-[[package]]
-name = "memchr"
-version = "2.5.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2dffe52ecf27772e601905b7522cb4ef790d2cc203488bbd0e2fe85fcb74566d"
-
 [[package]]
 name = "nb"
 version = "0.1.3"
@@ -267,7 +252,6 @@ dependencies = [
 name = "pi-transceiver-firmware"
 version = "0.1.0"
 dependencies = [
- "core2",
  "cortex-m",
  "cortex-m-rt",
  "cortex-m-rtic",

Cargo.toml

@@ -19,7 +19,6 @@ cortex-m = "0.7"
 cortex-m-rt = "0.7"
 #cortex-m-semihosting = "0.5"
 #panic-semihosting = "0.6"
-core2 = { version = "0.3", default_features = false }
 rf4463 = { path = "../rf4463" }
 cortex-m-rtic = { version = "1.1.4" }
 ringbuffer = { version = "0.13.0", default_features = false }