[AGPGART] Don't try to remap i810 registers on resume.

We don't unmap them on the suspend path, so on resume
trying to remap will fail, and then result in an
oops the next time something tries to access them.
Signed-off-by: Dave Jones <davej@redhat.com>

drivers/char/agp/intel-agp.c

@@ -124,13 +124,15 @@ static int intel_i810_configure(void)
 
 	current_size = A_SIZE_FIX(agp_bridge->current_size);
 
-	pci_read_config_dword(intel_i810_private.i810_dev, I810_MMADDR, &temp);
-	temp &= 0xfff80000;
-
-	intel_i810_private.registers = ioremap(temp, 128 * 4096);
 	if (!intel_i810_private.registers) {
-		printk(KERN_ERR PFX "Unable to remap memory.\n");
-		return -ENOMEM;
+		pci_read_config_dword(intel_i810_private.i810_dev, I810_MMADDR, &temp);
+		temp &= 0xfff80000;
+
+		intel_i810_private.registers = ioremap(temp, 128 * 4096);
+		if (!intel_i810_private.registers) {
+			printk(KERN_ERR PFX "Unable to remap memory.\n");
+			return -ENOMEM;
+		}
 	}
 
 	if ((readl(intel_i810_private.registers+I810_DRAM_CTL)