mm/mmap: rename __vma_unlink_common() to __vma_unlink()

__vma_unlink_common() and __vma_unlink() are counterparts.  Since there is
no function named __vma_unlink(), let's rename __vma_unlink_common() to
__vma_unlink() to make the code more self-explanatory and easy for
audience to understand.

Otherwise we may expect there are several variants of vma_unlink() and
__vma_unlink_common() is used by them.
Signed-off-by: NWei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Reviewed-by: NAndrew Morton <akpm@linux-foundation.org>
Link: https://lkml.kernel.org/r/20200809232057.23477-1-richard.weiyang@linux.alibaba.comSigned-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mm/mmap.c

@@ -677,7 +677,7 @@ static void __insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma)
 	mm->map_count++;
 }
 
-static __always_inline void __vma_unlink_common(struct mm_struct *mm,
+static __always_inline void __vma_unlink(struct mm_struct *mm,
 						struct vm_area_struct *vma,
 						struct vm_area_struct *ignore)
 {
@@ -859,7 +859,7 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
 		 * us to remove next before dropping the locks.
 		 */
 		if (remove_next != 3)
-			__vma_unlink_common(mm, next, next);
+			__vma_unlink(mm, next, next);
 		else
 			/*
 			 * vma is not before next if they've been
@@ -870,7 +870,7 @@ int __vma_adjust(struct vm_area_struct *vma, unsigned long start,
 			 * "next" (which is stored in post-swap()
 			 * "vma").
 			 */
-			__vma_unlink_common(mm, next, vma);
+			__vma_unlink(mm, next, vma);
 		if (file)
 			__remove_shared_vm_struct(next, file, mapping);
 	} else if (insert) {