powerpc/sysdev: Remove some duplicate prefix in some messages

At the beginning of the file, we have:
   #define pr_fmt(fmt) "xive: " fmt

So, there is no need to duplicate "XIVE:" in debug and error messages.

For the records, these useless prefix have been added in commit
5af50993 ("KVM: PPC: Book3S HV: Native usage of the XIVE interrupt
controller")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7b8b5915a2c7c1616b33e8433ebe0a0bf07070a2.1665312579.git.christophe.jaillet@wanadoo.fr

arch/powerpc/sysdev/xive/native.c

@@ -535,13 +535,13 @@ static bool __init xive_parse_provisioning(struct device_node *np)
 static void __init xive_native_setup_pools(void)
 {
 	/* Allocate a pool big enough */
-	pr_debug("XIVE: Allocating VP block for pool size %u\n", nr_cpu_ids);
+	pr_debug("Allocating VP block for pool size %u\n", nr_cpu_ids);
 
 	xive_pool_vps = xive_native_alloc_vp_block(nr_cpu_ids);
 	if (WARN_ON(xive_pool_vps == XIVE_INVALID_VP))
-		pr_err("XIVE: Failed to allocate pool VP, KVM might not function\n");
+		pr_err("Failed to allocate pool VP, KVM might not function\n");
 
-	pr_debug("XIVE: Pool VPs allocated at 0x%x for %u max CPUs\n",
+	pr_debug("Pool VPs allocated at 0x%x for %u max CPUs\n",
 		 xive_pool_vps, nr_cpu_ids);
 }