hv: coding style: use the defined data type __packed

1) Use __attribute__((packed)) instead of #pragma pack(1)
2) Use the defined data type __packed instead of __attribute__((packed))

Tracked-On: #861
Signed-off-by: Li, Fei1 <fei1.li@intel.com>

hypervisor/include/arch/x86/cpu.h

@@ -235,7 +235,7 @@ extern uint64_t               secondary_cpu_stack[1];
 struct descriptor_table {
 	uint16_t limit;
 	uint64_t base;
-} __attribute__((packed));
+} __packed;
 
 /* CPU states defined */
 enum pcpu_boot_state {

hypervisor/include/arch/x86/guest/vm0_boot.h

@@ -12,7 +12,7 @@ struct efi_context {
 	struct acrn_vcpu_regs vcpu_regs;
 	void *rsdp;
 	void *ap_trampoline_buf;
-}__attribute__((packed));
+} __packed;
 
 void *get_rsdp_from_uefi(void);
 void *get_ap_trampoline_buf(void);

hypervisor/include/arch/x86/mmu.h

@@ -172,8 +172,6 @@ void invept(const struct acrn_vcpu *vcpu);
 uint64_t *lookup_address(uint64_t *pml4_page, uint64_t addr,
 		uint64_t *pg_size, const struct memory_ops *mem_ops);
 
-#pragma pack(1)
-
 /** Defines a single entry in an E820 memory map. */
 struct e820_entry {
    /** The base address of the memory range. */
@@ -182,9 +180,7 @@ struct e820_entry {
 	uint64_t length;
    /** The type of memory region. */
 	uint32_t type;
-};
-
-#pragma pack()
+} __packed;
 
 /* E820 memory types */
 #define E820_TYPE_RAM		1U	/* EFI 1, 2, 3, 4, 5, 6, 7 */

hypervisor/include/arch/x86/per_cpu.h

@@ -55,7 +55,7 @@ struct per_cpu_region {
 #endif
 } __aligned(PAGE_SIZE); /* per_cpu_region size aligned with PAGE_SIZE */
 
-extern struct per_cpu_region per_cpu_data[];
+extern struct per_cpu_region per_cpu_data[CONFIG_MAX_PCPU_NUM];
 /*
  * get percpu data for pcpu_id.
  */

hypervisor/include/public/acrn_common.h

@@ -394,7 +394,7 @@ struct acrn_descriptor_ptr {
 	uint16_t limit;
 	uint64_t base;
 	uint16_t reserved[3];   /* align struct size to 64bit */
-} __attribute__((packed));
+} __packed;
 
 /**
  * @brief registers info for vcpu.