[docs] x/mint - general audit and cleanup (#8267)

* update docs

* update docs

* review changes

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

x/mint/spec/02_state.md

@@ -8,28 +8,14 @@ order: 2
 
 The minter is a space for holding current inflation information.
 
- - Minter: `0x00 -> amino(minter)`
+ - Minter: `0x00 -> ProtocolBuffer(minter)`
 
-```go
-type Minter struct {
-	Inflation        sdk.Dec   // current annual inflation rate
-	AnnualProvisions sdk.Dec   // current annual exptected provisions
-}
-```
++++ https://github.com/cosmos/cosmos-sdk/blob/v0.40.0-rc7/proto/cosmos/mint/v1beta1/mint.proto#L8-L19
 
 ## Params
 
 Minting params are held in the global params store. 
 
- - Params: `mint/params -> amino(params)`
+ - Params: `mint/params -> legacy_amino(params)`
 
-```go
-type Params struct {
-	MintDenom           string  // type of coin to mint
-	InflationRateChange sdk.Dec // maximum annual change in inflation rate
-	InflationMax        sdk.Dec // maximum inflation rate
-	InflationMin        sdk.Dec // minimum inflation rate
-	GoalBonded          sdk.Dec // goal of percent bonded atoms
-	BlocksPerYear       uint64   // expected blocks per year
-}
-```
++++ https://github.com/cosmos/cosmos-sdk/blob/v0.40.0-rc7/proto/cosmos/mint/v1beta1/mint.proto#L21-L53