ata: pata_via: fix sloppy typing in via_do_set_mode()

The local variables 'T' and 'UT' are needlessly declared as *unsigned*
*long* -- the corresponding parameters of ata_timing_compute() are both
declared as *int*.  While fixing up those declarations, also make the
'via_clock' and 'T' variables *const* as they are never re-assigned
after initialization -- the object code should remain the same as gcc
previously used copy propagation anyway...

Found by Linux Verification Center (linuxtesting.org) with the SVACE static
analysis tool.
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

drivers/ata/pata_via.c

@@ -248,9 +248,9 @@ static void via_do_set_mode(struct ata_port *ap, struct ata_device *adev,
 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 	struct ata_device *peer = ata_dev_pair(adev);
 	struct ata_timing t, p;
-	static int via_clock = 33333;	/* Bus clock in kHZ */
-	unsigned long T =  1000000000 / via_clock;
-	unsigned long UT = T;
+	const int via_clock = 33333;	/* Bus clock in kHz */
+	const int T = 1000000000 / via_clock;
+	int UT = T;
 	int ut;
 	int offset = 3 - (2*ap->port_no) - adev->devno;