sparc32: always define boot_cpu_id

Define boot_cpu_id in single-processor kernels as well. This is
to support architectures which can boot on other than CPU0.

Sam Ravnborg has written the cleanup parts by extracting
boot_cpu_id from smp_32.c into setup_32.c and cleaned up
sun4d_irq.c.

boot_cpu_id was initialized before BSS was cleared in
sun4c_continue_boot, instead boot_cpu_id is set to 0xff to
avoid BSS. If boot_cpu_id is untouched (0xff) by bootup code
it will be overwritten to 0. boot_cpu_id4 is automatically
calculated in common code.

Signed-off-by: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/kernel/setup_32.c b/arch/sparc/kernel/setup_32.c
index ef8a2ed..3609bde 100644
--- a/arch/sparc/kernel/setup_32.c
+++ b/arch/sparc/kernel/setup_32.c
@@ -103,6 +103,10 @@
 /* Exported for mm/init.c:paging_init. */
 unsigned long cmdline_memory_size __initdata = 0;
 
+/* which CPU booted us (0xff = not set) */
+unsigned char boot_cpu_id = 0xff; /* 0xff will make it into DATA section... */
+unsigned char boot_cpu_id4; /* boot_cpu_id << 2 */
+
 static void
 prom_console_write(struct console *con, const char *s, unsigned n)
 {