mm, page_flags: remove PG_slob_free

With SLOB removed we no longer need the PG_slob_free alias for
PG_private. Also update tools/mm/page-types.

Signed-off-by: Vlastimil Babka <[e-mail]>
Acked-by: Hyeonggon Yoo <[e-mail]>
Acked-by: Lorenzo Stoakes <[e-mail]>
Acked-by: Mike Rapoport (IBM) <[e-mail]>

include/linux/page-flags.h

···
 	/* Remapped by swiotlb-xen. */
 	PG_xen_remapped = PG_owner_priv_1,
 
-	/* SLOB */
-	PG_slob_free = PG_private,
-
 #ifdef CONFIG_MEMORY_FAILURE
 	/*
 	 * Compound pages. Stored in first tail page's flags.
···
 PAGEFLAG(Workingset, workingset, PF_HEAD)
 	TESTCLEARFLAG(Workingset, workingset, PF_HEAD)
 __PAGEFLAG(Slab, slab, PF_NO_TAIL)
-__PAGEFLAG(SlobFree, slob_free, PF_NO_TAIL)
 PAGEFLAG(Checked, checked, PF_NO_COMPOUND)	   /* Used by some filesystems */
 
 /* Xen */

tools/mm/page-types.c

···
  */
 #define KPF_ANON_EXCLUSIVE	47
 #define KPF_READAHEAD		48
-#define KPF_SLOB_FREE		49
 #define KPF_SLUB_FROZEN		50
 #define KPF_SLUB_DEBUG		51
 #define KPF_FILE		61
···
 
 	[KPF_ANON_EXCLUSIVE]	= "d:anon_exclusive",
 	[KPF_READAHEAD]		= "I:readahead",
-	[KPF_SLOB_FREE]		= "P:slob_free",
 	[KPF_SLUB_FROZEN]	= "A:slub_frozen",
 	[KPF_SLUB_DEBUG]	= "E:slub_debug",
 
···
 	if ((flags & BIT(ANON)) && (flags & BIT(MAPPEDTODISK)))
 		flags ^= BIT(MAPPEDTODISK) | BIT(ANON_EXCLUSIVE);
 
-	/* SLOB/SLUB overload several page flags */
+	/* SLUB overloads several page flags */
 	if (flags & BIT(SLAB)) {
-		if (flags & BIT(PRIVATE))
-			flags ^= BIT(PRIVATE) | BIT(SLOB_FREE);
 		if (flags & BIT(ACTIVE))
 			flags ^= BIT(ACTIVE) | BIT(SLUB_FROZEN);
 		if (flags & BIT(ERROR))