ide: remove duplicated assignment to 'cursg'

Pointer cursg is initialized to cmd->cursg and again re-assigned the
same value a few lines later, hence the second assignment is redundant
and can be removed.

Cleans up clang warning:
drivers/ide/ide-taskfile.c:229:22: warning: Value stored to 'cursg'
during its initialization is never read
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/ide/ide-taskfile.c

@@ -232,7 +232,6 @@ void ide_pio_bytes(ide_drive_t *drive, struct ide_cmd *cmd,
 	unsigned int offset;
 	u8 *buf;
 
-	cursg = cmd->cursg;
 	if (cursg == NULL)
 		cursg = cmd->cursg = sg;