xen/vpci: Fix msix existing mapping printk

The format string lacks a space, so mfn and type run together:
(XEN) d0v0 0000:06:00.7: existing mapping (mfn: 753037type: 0) at 0x1 clobbers MSIX MMIO area

Add a space.  Additionally, move the format string to a single long line
to improve grep-ability.

Fixes: 677053fac1 ("vpci/msix: carve p2m hole for MSIX MMIO regions")
Signed-off-by: Jason Andryuk <jason.andryuk@amd.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>

xen/drivers/vpci/msix.c

@@ -665,8 +665,7 @@ int vpci_make_msix_hole(const struct pci_dev *pdev)
             default:
                 put_gfn(d, start);
                 gprintk(XENLOG_WARNING,
-                        "%pp: existing mapping (mfn: %" PRI_mfn
-                        "type: %d) at %#lx clobbers MSIX MMIO area\n",
+                        "%pp: existing mapping (mfn: %" PRI_mfn " type: %d) at %#lx clobbers MSIX MMIO area\n",
                         &pdev->sbdf, mfn_x(mfn), t, start);
                 return -EEXIST;
             }