[PATCH 5/8] acpi: fix gcc9 error address-of-packed-member

[Michael Chang]

Add missing GRUB_PACKED attribute to struct grub_acpi_madt.

The solved gcc9 error like this.

[  233s] ../../grub-core/commands/lsacpi.c: In function 'disp_acpi_xsdt_table':
[  233s] ../../grub-core/commands/lsacpi.c:201:27: error: converting a packed 
'struct grub_acpi_table_header' pointer (alignment 1) to a 'struct 
grub_acpi_madt' pointer (alignment 4) may result in an unaligned pointer value 
[-Werror=address-of-packed-member]
[  233s]   201 |  disp_madt_table ((struct grub_acpi_madt *) t);
[  233s]       |                           ^~~~~~~~~~~~~~
[  233s] In file included from ../../grub-core/commands/lsacpi.c:23:
[  233s] ../../include/grub/acpi.h:50:8: note: defined here
[  233s]    50 | struct grub_acpi_table_header
[  233s]       |        ^~~~~~~~~~~~~~~~~~~~~~
[  233s] ../../include/grub/acpi.h:90:8: note: defined here
[  233s]    90 | struct grub_acpi_madt
[  233s]       |        ^~~~~~~~~~~~~~
[  233s] ../../grub-core/commands/lsacpi.c: In function 'disp_acpi_rsdt_table':
[  233s] ../../grub-core/commands/lsacpi.c:225:27: error: converting a packed 
'struct grub_acpi_table_header' pointer (alignment 1) to a 'struct 
grub_acpi_madt' pointer (alignment 4) may result in an unaligned pointer value 
[-Werror=address-of-packed-member]
[  233s]   225 |  disp_madt_table ((struct grub_acpi_madt *) t);
[  233s]       |                           ^~~~~~~~~~~~~~
[  233s] In file included from ../../grub-core/commands/lsacpi.c:23:
[  233s] ../../include/grub/acpi.h:50:8: note: defined here
[  233s]    50 | struct grub_acpi_table_header
[  233s]       |        ^~~~~~~~~~~~~~~~~~~~~~
[  233s] ../../include/grub/acpi.h:90:8: note: defined here
[  233s]    90 | struct grub_acpi_madt
[  233s]       |        ^~~~~~~~~~~~~~

Signed-off-by: Michael Chang <address@hidden>
---
 include/grub/acpi.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/grub/acpi.h b/include/grub/acpi.h
index 66148f684..84f49487d 100644
--- a/include/grub/acpi.h
+++ b/include/grub/acpi.h
@@ -93,7 +93,7 @@ struct grub_acpi_madt
   grub_uint32_t lapic_addr;
   grub_uint32_t flags;
   struct grub_acpi_madt_entry_header entries[0];
-};
+} GRUB_PACKED;
 
 enum
   {
-- 
2.16.4