net/packet: remove unused PGV_FROM_VMALLOC definition.

This patch removes the definition of PGV_FROM_VMALLOC from af_packet.c.
The PGV_FROM_VMALLOC definition was already removed by
commit 441c793a5650 ("net: cleanup unused macros in net directory"),
and its usage was removed even before by commit c56b4d90123b
("af_packet: remove pgv.flags"); but it was added back by mistake later on,
in commit f6fb8f100b80 ("af-packet: TPACKET_V3 flexible buffer implementation").

Signed-off-by: Rami Rosen <rami.rosen@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/packet/af_packet.c

@@ -177,8 +177,6 @@ static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
 #define BLK_PLUS_PRIV(sz_of_priv) \
 	(BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
 
-#define PGV_FROM_VMALLOC 1
-
 #define BLOCK_STATUS(x)	((x)->hdr.bh1.block_status)
 #define BLOCK_NUM_PKTS(x)	((x)->hdr.bh1.num_pkts)
 #define BLOCK_O2FP(x)		((x)->hdr.bh1.offset_to_first_pkt)