[decompiler] fix missing casts issue (#573)

* fix casts issue

* fix bug

* one last small fix

test/decompiler/reference/engine/camera/camera-h_REF.gc

@@ -842,5 +842,5 @@
   )
 
 ;; failed to figure out what this is:
-(let ((v0-11 0))
+(let ((v0-28 0))
   )

test/decompiler/reference/engine/camera/math-camera-h_REF.gc

@@ -191,6 +191,5 @@
   )
 
 ;; failed to figure out what this is:
-(let ((v0-3 0))
+(let ((v0-6 0))
   )
-

test/decompiler/reference/engine/camera/math-camera_REF.gc

@@ -145,8 +145,7 @@
     )
    )
   (fog-corrector-setup *math-camera-fog-correction* math-cam)
-  (let ((v0-1 (matrix-identity! (-> math-cam camera-rot))))
-   )
+  (matrix-identity! (-> math-cam camera-rot))
   (let ((fog-constant-1 100.0)
         (fog-constant-2 16760631.0)
         )

test/decompiler/reference/engine/camera/pov-camera-h_REF.gc

@@ -47,9 +47,5 @@
   )
 
 ;; failed to figure out what this is:
-(let ((v0-1 0))
+(let ((v0-2 0))
   )
-
-
-
-