ide serverworks warning fixes

gcc-4.3:

drivers/ide/pci/serverworks.c: In function 'svwks_tune_chipset':
drivers/ide/pci/serverworks.c:176: warning: overflow in implicit constant conversion
drivers/ide/pci/serverworks.c:190: warning: overflow in implicit constant conversion
drivers/ide/pci/serverworks.c:211: warning: overflow in implicit constant conversion
drivers/ide/pci/serverworks.c:212: warning: overflow in implicit constant conversion

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

drivers/ide/pci/serverworks.c

@@ -179,7 +179,7 @@ dma_pio:
 				   ((dma_stat&(1<<(5+unit)))==(1<<(5+unit)))) {
 				u8 dmaspeed = dma_timing;
 
-				dma_timing &= ~0xFF;
+				dma_timing &= ~0xFFU;
 				if ((dmaspeed & 0x20) == 0x20)
 					dmaspeed = XFER_MW_DMA_2;
 				else if ((dmaspeed & 0x21) == 0x21)
@@ -193,7 +193,7 @@ dma_pio:
 			} else if (pio_timing) {
 				u8 piospeed = pio_timing;
 
-				pio_timing &= ~0xFF;
+				pio_timing &= ~0xFFU;
 				if ((piospeed & 0x20) == 0x20)
 					piospeed = XFER_PIO_4;
 				else if ((piospeed & 0x22) == 0x22)
@@ -214,8 +214,8 @@ dma_pio:
 
 oem_setup_failed:
 
-	pio_timing	&= ~0xFF;
-	dma_timing	&= ~0xFF;
+	pio_timing	&= ~0xFFU;
+	dma_timing	&= ~0xFFU;
 	ultra_timing	&= ~(0x0F << (4*unit));
 	ultra_enable	&= ~(0x01 << drive->dn);
 	csb5_pio	&= ~(0x0F << (4*drive->dn));