Use binary operator for decidable equality consistently

Signed-off-by: Danila Fedorin <danila.fedorin@gmail.com>

Lattice/FiniteMap.agda

@@ -7,11 +7,11 @@ open import Data.List using (List; _∷_; [])
 module Lattice.FiniteMap {A : Set} {B : Set}
     {_≈₂_ : B → B → Set}
     {_⊔₂_ : B → B → B} {_⊓₂_ : B → B → B}
-    (≡-dec-A : IsDecidable (_≡_ {_} {A}))
+    (≡-Decidable-A : IsDecidable {_} {A} _≡_)
     (lB : IsLattice B _≈₂_ _⊔₂_ _⊓₂_) where
 
 open IsLattice lB using () renaming (_≼_ to _≼₂_)
-open import Lattice.Map ≡-dec-A lB as Map
+open import Lattice.Map ≡-Decidable-A lB as Map
     using
         ( Map
         ; ⊔-equal-keys