cpu/x86: Move smm_lock() prototype

The function implementations are in local platform
scopes.

Change-Id: I7a3025398b15fe6d2c5a13cdb65f3e62a49c0bc6
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34151
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Furquan Shaikh <furquan@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/cpu/intel/haswell/haswell.h

@@ -166,6 +166,7 @@ void smm_info(uintptr_t *perm_smbase, size_t *perm_smsize,
 		size_t *smm_save_state_size);
 void smm_initialize(void);
 void smm_relocate(void);
+void smm_lock(void);
 struct bus;
 void bsp_init_and_start_aps(struct bus *cpu_bus);
 /* Determine if HyperThreading is disabled. The variable is not valid until

src/cpu/intel/smm/gen1/smi.h

@@ -31,3 +31,4 @@ void southbridge_smm_clear_state(void);
 void smm_relocation_handler(int cpu, uintptr_t curr_smbase,
 			uintptr_t staggered_smbase);
 void smm_relocate(void);
+void smm_lock(void);