vmcoreinfo: Remove documentation of PG_slab and PG_hugetlb

The changes to kernel/vmcore_info.c were sadly not reflected in the
documentation. Rectify that for both these flags as well as adding
PAGE_UNACCEPTED_MAPCOUNT_VALUE.

Signed-off-by: Matthew Wilcox (Oracle) <[e-mail]>
Acked-by: Harry Yoo <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Vlastimil Babka <[e-mail]>

Documentation/admin-guide/kdump/vmcoreinfo.rst

···
 On linux-2.6.21 or later, the number of free pages is in
 vm_stat[NR_FREE_PAGES]. Used to get the number of free pages.
 
-PG_lru|PG_private|PG_swapcache|PG_swapbacked|PG_slab|PG_hwpoision|PG_head_mask|PG_hugetlb
------------------------------------------------------------------------------------------
+PG_lru|PG_private|PG_swapcache|PG_swapbacked|PG_hwpoison|PG_head_mask
+--------------------------------------------------------------------------
 
 Page attributes. These flags are used to filter various unnecessary for
 dumping pages.
 
-PAGE_BUDDY_MAPCOUNT_VALUE(~PG_buddy)|PAGE_OFFLINE_MAPCOUNT_VALUE(~PG_offline)|PAGE_OFFLINE_MAPCOUNT_VALUE(~PG_unaccepted)
--------------------------------------------------------------------------------------------------------------------------
+PAGE_SLAB_MAPCOUNT_VALUE|PAGE_BUDDY_MAPCOUNT_VALUE|PAGE_OFFLINE_MAPCOUNT_VALUE|PAGE_HUGETLB_MAPCOUNT_VALUE|PAGE_UNACCEPTED_MAPCOUNT_VALUE
+------------------------------------------------------------------------------------------------------------------------------------------
 
 More page attributes. These flags are used to filter various unnecessary for
 dumping pages.