Revert "Use broadcast SIPI to startup siblings"

This reverts commit 042c1461fb.

It turned out that sending IPIs via broadcast doesn't work on
Sandybridge. We tried to come up with a solution, but didn't
found any so far. So revert the code for now until we have
a working solution.

Change-Id: I7dd1cba5a4c1e4b0af366b20e8263b1f6f4b9714
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Reviewed-on: http://review.coreboot.org/1381
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/include/cpu/cpu.h

@@ -4,12 +4,10 @@
 #include <arch/cpu.h>
 
 #if !defined(__ROMCC__)
-void cpu_initialize(struct bus *cpu_bus, int index);
+void cpu_initialize(void);
 struct bus;
 void initialize_cpus(struct bus *cpu_bus);
-void secondary_cpu_init(int index);
-
-extern unsigned int cpucount;
+void secondary_cpu_init(void);
 
 #if !CONFIG_WAIT_BEFORE_CPUS_INIT
 	#define cpus_ready_for_init() do {} while(0)