[SPARC32]: Revert f642b263.

This causes boot failures for some people.
It looks like in fact that some SILO provided
ramdisk images should not be KERNBASE normalized.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

arch/sparc/mm/init.c

@@ -206,7 +206,8 @@ unsigned long __init bootmem_init(unsigned long *pages_avail)
 #ifdef CONFIG_BLK_DEV_INITRD
 	/* Now have to check initial ramdisk, so that bootmap does not overwrite it */
 	if (sparc_ramdisk_image) {
-		sparc_ramdisk_image -= KERNBASE;
+		if (sparc_ramdisk_image >= (unsigned long)&_end - 2 * PAGE_SIZE)
+			sparc_ramdisk_image -= KERNBASE;
 		initrd_start = sparc_ramdisk_image + phys_base;
 		initrd_end = initrd_start + sparc_ramdisk_size;
 		if (initrd_end > end_of_phys_memory) {