mm: rmap: Fix invalid casting from a void to an enumerator.

fixes:

../mm/rmap.c:1344:25: warning: cast to smaller integer type 'enum ttu_flags' from 'void *' [-Wvoid-pointer-to-enum-cast]
        enum ttu_flags flags = (enum ttu_flags)arg;
                               ^~~~~~~~~~~~~~~~~~~

Signed-off-by: techyminati <[email protected]>
Signed-off-by: Jyotiraditya Panda <[email protected]>
Signed-off-by: Sarthak Roy <[email protected]>
Signed-off-by: Cyber Knight <[email protected]>
Signed-off-by: ManshuTyagi <[email protected]>
Signed-off-by: Nishant Kumar <[email protected]>
Signed-off-by: nishant6342 <[email protected]>

mm/rmap.c

@@ -1402,7 +1402,7 @@ static bool try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 	struct page *subpage;
 	bool ret = true;
 	unsigned long start = address, end;
-	enum ttu_flags flags = (enum ttu_flags)arg;
+	enum ttu_flags flags = (enum ttu_flags)(long)arg;
 
 	/* munlock has nothing to gain from examining un-locked vmas */
 	if ((flags & TTU_MUNLOCK) && !(vma->vm_flags & VM_LOCKED))