cpu/cpu.h: Change the function signature

There is no need to pass the CPU index around.

Change-Id: Iad8e3cb318e6520ac5877118dbf43597dedb75b9
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/69504
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Elyes Haouas <ehaouas@noos.fr>

src/include/cpu/cpu.h

@@ -6,7 +6,7 @@
 #include <arch/cpu.h>  /* IWYU pragma: export */
 #include <stdint.h>
 
-void cpu_initialize(unsigned int cpu_index);
+void cpu_initialize(void);
 /* Returns default APIC id based on logical_cpu number or < 0 on failure. */
 int cpu_get_apic_id(int logical_cpu);
 uintptr_t cpu_get_lapic_addr(void);