fix copy_a deallocation

Author: perazz

src/stdlib_linalg_determinant.fypp

@@ -224,7 +224,7 @@ submodule (stdlib_linalg) stdlib_linalg_determinant
                        err0 = linalg_state_type(this,LINALG_INTERNAL_ERROR,'catastrophic error')
                 end select
 
-                if (.not.copy_a) deallocate(amat)
+                if (copy_a) deallocate(amat)
 
          end select