modularization: hypervisor initilization component

hypervisor initilization component triggered by boot component,
and it calls different components initilization functions from
the highest layer.

this patch added init.c and move reorged cpu init functions into
it, keep hardware management functions in cpu.c but move other
components' init function into init.c.

the hypervisor initilization components will call:
- init_cpu_pre
- init_cpu_post
- init_bsp
- init_debug_pre
- init_debug_post
- init_guest
- init_passthru
- enter_guest_mode

the hypervisor initilization component include files:
arch/x86/init.c
include/arch/x86/init.h

this component is higest layer, so there is no reverse dependencies for it.

v2:
- separate into 2 patches, 1 for reorg, 1 for pure move.

Tracked-On: #1842
Signed-off-by: Jason Chen CJ <jason.cj.chen@intel.com>
Acked-by: Xu, Anthony <anthony.xu@intel.com>

hypervisor/include/arch/x86/cpu.h

@@ -127,9 +127,6 @@
 /* Boot CPU ID */
 #define BOOT_CPU_ID             0U
 
-/* hypervisor stack bottom magic('intl') */
-#define SP_BOTTOM_MAGIC    0x696e746cUL
-
 /* type of speculation control
  * 0 - no speculation control support
  * 1 - raw IBRS + IPBP support
@@ -317,8 +314,8 @@ bool is_apicv_posted_intr_supported(void);
 bool is_ept_supported(void);
 bool cpu_has_cap(uint32_t bit);
 void load_cpu_state_data(void);
-void bsp_boot_init(void);
-void cpu_secondary_init(void);
+void init_cpu_pre(uint16_t pcpu_id);
+void init_cpu_post(uint16_t pcpu_id);
 void start_cpus(void);
 void stop_cpus(void);
 void wait_sync_change(uint64_t *sync, uint64_t wake_sync);

hypervisor/include/arch/x86/init.h

@@ -0,0 +1,14 @@
+/*
+ * Copyright (C) <2018> Intel Corporation
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef	INIT_H
+
+/* hypervisor stack bottom magic('intl') */
+#define SP_BOTTOM_MAGIC    0x696e746cUL
+
+void bsp_boot_init(void);
+void cpu_secondary_init(void);
+
+#endif /* INIT_H*/