Removed useless copies in det functions

src/algebra/TinyMatrix.hpp

@@ -336,8 +336,6 @@ KOKKOS_INLINE_FUNCTION
 T det(const TinyMatrix<1,T>& A)
 {
   static_assert(std::is_arithmetic<T>::value, "determinent is not defined for non arithmetic types");
-  TinyMatrix<1,T> M=A;
-
   return A(0,0);
 }
 
@@ -346,8 +344,6 @@ KOKKOS_INLINE_FUNCTION
 T det(const TinyMatrix<2,T>& A)
 {
   static_assert(std::is_arithmetic<T>::value, "determinent is not defined for non arithmetic types");
-  TinyMatrix<2,T> M=A;
-
   return A(0,0)*A(1,1)-A(1,0)*A(0,1);
 }
 
@@ -356,8 +352,6 @@ KOKKOS_INLINE_FUNCTION
 T det(const TinyMatrix<3,T>& A)
 {
   static_assert(std::is_arithmetic<T>::value, "determinent is not defined for non arithmetic types");
-  TinyMatrix<3,T> M=A;
-
   return
     A(0,0)*(A(1,1)*A(2,2)-A(2,1)*A(1,2))
     -A(1,0)*(A(0,1)*A(2,2)-A(2,1)*A(0,2))