hv: remove CONFIG_PARTITION_MODE for pre-launched VM vE820 creation

Preparing for hybrid mode:

- create vE820 for pre-launched VMs and do other init code when the
  vm_config->type is PRE_LAUNCHED_VM.
- create ve820.c for each board because without wrapping by
  CONFIG_PARTITION_MODE, ve820_entry[] needs to be visible even when
  compiling target boards that haven't enabled pre-launched VMs.
- remove create_prelaunched_vm_e820() from vm.c and implement board
  specific function for each $(CONFIG_BOARD)/ve820.c. The reasons being:
  - don't need to define ve820_entry[32] for those boards that don't
    support pre-launched VMs.
  - more importantly, this makes it much easier to create different per-VM
    vE820 when it's needed.

Tracked-On: #2291
Signed-off-by: Zide Chen <zide.chen@intel.com>

hypervisor/include/arch/x86/board.h

@@ -8,6 +8,9 @@
 
 #include <types.h>
 
+/* forward declarations */
+struct acrn_vm;
+
 struct platform_clos_info {
 	uint32_t clos_mask;
 	uint32_t msr_index;
@@ -16,4 +19,7 @@ struct platform_clos_info {
 extern struct platform_clos_info platform_clos_array[];
 extern uint16_t platform_clos_num;
 
+/* board specific functions */
+void create_prelaunched_vm_e820(struct acrn_vm *vm);
+
 #endif /* BOARD_H */

hypervisor/include/arch/x86/e820.h

@@ -34,8 +34,6 @@ struct e820_mem_params {
 	uint64_t total_mem_size;
 };
 
-extern const struct e820_entry ve820_entry[E820_MAX_ENTRIES];
-
 /* HV read multiboot header to get e820 entries info and calc total RAM info */
 void init_e820(void);