vPCI: resolve MISRA R10.1 boolean arithmetic type violation

MISRA C Rule 10.1 states: "Operands shall not be of an inappropriate
essential type".

bar_write() and guest_mem_bar_write() added the boolean 'hi' to a
pointer difference when printing the ignored BAR index. These handlers
are registered only for the memory BAR registers, so print
(reg - PCI_BASE_ADDRESS_0) / 4 instead. The expression has type
unsigned int, so use %u.

No functional changes.

Suggested-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Dmytro Prokopchuk <dmytro_prokopchuk1@epam.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger@xenproject.org>

xen/drivers/vpci/header.c

@@ -585,8 +585,8 @@ static void cf_check bar_write(
         /* If the value written is the current one avoid printing a warning. */
         if ( val != (uint32_t)(bar->addr >> (hi ? 32 : 0)) )
             gprintk(XENLOG_WARNING,
-                    "%pp: ignored BAR %zu write while mapped\n",
+                    "%pp: ignored BAR %u write while mapped\n",
-                    &pdev->sbdf, bar - pdev->vpci->header.bars + hi);
+                    &pdev->sbdf, (reg - PCI_BASE_ADDRESS_0) / 4);
         return;
     }
 
@@ -646,8 +646,8 @@ static void cf_check guest_mem_bar_write(const struct pci_dev *pdev,
         /* If the value written is the current one avoid printing a warning. */
         if ( guest_addr != bar->guest_addr )
             gprintk(XENLOG_WARNING,
-                    "%pp: ignored guest BAR %zu write while mapped\n",
+                    "%pp: ignored guest BAR %u write while mapped\n",
-                    &pdev->sbdf, bar - pdev->vpci->header.bars + hi);
+                    &pdev->sbdf, (reg - PCI_BASE_ADDRESS_0) / 4);
         return;
     }
     bar->guest_addr = guest_addr;