agp: remove unused variable mcapndx

This patch fix the following warning:
drivers/char/agp/isoch.c: In function ‘agp_3_5_isochronous_node_enable’:
drivers/char/agp/isoch.c:87:5: warning: variable ‘mcapndx’ set but not
used [-Wunused-but-set-variable]
  u8 mcapndx;
     ^~~~~~~
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/char/agp/isoch.c

@@ -84,7 +84,6 @@ static int agp_3_5_isochronous_node_enable(struct agp_bridge_data *bridge,
 	unsigned int cdev = 0;
 	u32 mnistat, tnistat, tstatus, mcmd;
 	u16 tnicmd, mnicmd;
-	u8 mcapndx;
 	u32 tot_bw = 0, tot_n = 0, tot_rq = 0, y_max, rq_isoch, rq_async;
 	u32 step, rem, rem_isoch, rem_async;
 	int ret = 0;
@@ -138,8 +137,6 @@ static int agp_3_5_isochronous_node_enable(struct agp_bridge_data *bridge,
 		cur = list_entry(pos, struct agp_3_5_dev, list);
 		dev = cur->dev;
 
-		mcapndx = cur->capndx;
-
 		pci_read_config_dword(dev, cur->capndx+AGPNISTAT, &mnistat);
 
 		master[cdev].maxbw = (mnistat >> 16) & 0xff;
@@ -251,8 +248,6 @@ static int agp_3_5_isochronous_node_enable(struct agp_bridge_data *bridge,
 		cur = master[cdev].dev;
 		dev = cur->dev;
 
-		mcapndx = cur->capndx;
-
 		master[cdev].rq += (cdev == ndevs - 1)
 		              ? (rem_async + rem_isoch) : step;