mm: fix kernel-doc function notation

Delete excess kernel-doc notation in mm/ subdirectory.
Actually this is a kernel-doc notation fix.

Warning(/var/linsrc/linux-2.6.27-git10//mm/vmalloc.c:902): Excess function parameter or struct member 'returns' description in 'vm_map_ram'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/vmalloc.c

@@ -897,7 +897,8 @@ EXPORT_SYMBOL(vm_unmap_ram);
  * @count: number of pages
  * @node: prefer to allocate data structures on this node
  * @prot: memory protection to use. PAGE_KERNEL for regular RAM
- * @returns: a pointer to the address that has been mapped, or NULL on failure
+ *
+ * Returns: a pointer to the address that has been mapped, or %NULL on failure
  */
 void *vm_map_ram(struct page **pages, unsigned int count, int node, pgprot_t prot)
 {