powerpc/papr_scm: Fix resource end address

Fix an off-by-one error in the memory resource range. This resource is
used to determine the address range of the memory to be hot-plugged as
ZONE_DEVICE memory. The current end address results in the kernel
attempting to map an additional memblock and the hypervisor may reject
the mapping resulting in the entire hot-plug failing.

Fixes: b5beae5 ("powerpc/pseries: Add driver for PAPR SCM regions")
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/platforms/pseries/papr_scm.c

@@ -296,7 +296,7 @@ static int papr_scm_probe(struct platform_device *pdev)
 
 	/* setup the resource for the newly bound range */
 	p->res.start = p->bound_addr;
-	p->res.end   = p->bound_addr + p->blocks * p->block_size;
+	p->res.end   = p->bound_addr + p->blocks * p->block_size - 1;
 	p->res.name  = pdev->name;
 	p->res.flags = IORESOURCE_MEM;