PCI: Fix incorrect vgaarb conditional in WARN_ON()

3448a19d "vgaarb: use bridges to control VGA routing where possible"
added the "flags & PCI_VGA_STATE_CHANGE_DECODES" condition to an existing
WARN_ON(), but used bitwise AND (&) instead of logical AND (&&), so the
condition is never true.  Replace with logical AND.

Found by Coverity (CID 142811).

Fixes: 3448a19d "vgaarb: use bridges to control VGA routing where possible"
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: David Airlie <airlied@redhat.com>

drivers/pci/pci.c

@@ -4125,7 +4125,7 @@ int pci_set_vga_state(struct pci_dev *dev, bool decode,
 	u16 cmd;
 	int rc;
 
-	WARN_ON((flags & PCI_VGA_STATE_CHANGE_DECODES) & (command_bits & ~(PCI_COMMAND_IO|PCI_COMMAND_MEMORY)));
+	WARN_ON((flags & PCI_VGA_STATE_CHANGE_DECODES) && (command_bits & ~(PCI_COMMAND_IO|PCI_COMMAND_MEMORY)));
 
 	/* ARCH specific VGA enables */
 	rc = pci_set_vga_state_arch(dev, decode, command_bits, flags);