SLUB: remove useless masking of GFP_ZERO

Remove a recently added useless masking of GFP_ZERO. GFP_ZERO is already
masked out in new_slab() (See how it calls allocate_slab). No need to do
it twice.

This reverts the SLUB parts of 7fd272550bd43cc1d7289ef0ab2fa50de137e767.

Cc: Matt Mackall <[e-mail]>
Reviewed-by: Pekka Enberg <[e-mail]>
Signed-off-by: Christoph Lameter <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

mm/slub.c

···
 	void **object;
 	struct page *new;
 
-	/* We handle __GFP_ZERO in the caller */
-	gfpflags &= ~__GFP_ZERO;
-
 	if (!c->page)
 		goto new_slab;