virtchnl: Add missing explicit padding to structures

On e.g. m68k, the alignment of 32-bit values is only 2 bytes, leading
to the following:

./include/linux/avf/virtchnl.h:147:36: warning: division by zero [-Wdiv-by-zero]
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:577:1: note: in expansion of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
VIRTCHNL_CHECK_STRUCT_LEN(272, virtchnl_filter);
^~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:577:32: error: enumerator value for ‘virtchnl_static_assert_virtchnl_filter’ is not an integer constant
VIRTCHNL_CHECK_STRUCT_LEN(272, virtchnl_filter);
^~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:147:53: note: in definition of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:147:36: warning: division by zero [-Wdiv-by-zero]
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:619:1: note: in expansion of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
VIRTCHNL_CHECK_STRUCT_LEN(16, virtchnl_pf_event);
^~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:619:31: error: enumerator value for ‘virtchnl_static_assert_virtchnl_pf_event’ is not an integer constant
VIRTCHNL_CHECK_STRUCT_LEN(16, virtchnl_pf_event);
^~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:147:53: note: in definition of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:147:36: warning: division by zero [-Wdiv-by-zero]
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:640:1: note: in expansion of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
VIRTCHNL_CHECK_STRUCT_LEN(12, virtchnl_iwarp_qv_info);
^~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:640:31: error: enumerator value for ‘virtchnl_static_assert_virtchnl_iwarp_qv_info’ is not an integer constant
VIRTCHNL_CHECK_STRUCT_LEN(12, virtchnl_iwarp_qv_info);
^~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:147:53: note: in definition of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:147:36: warning: division by zero [-Wdiv-by-zero]
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^
./include/linux/avf/virtchnl.h:647:1: note: in expansion of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
VIRTCHNL_CHECK_STRUCT_LEN(16, virtchnl_iwarp_qvlist_info);
^~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:647:31: error: enumerator value for ‘virtchnl_static_assert_virtchnl_iwarp_qvlist_info’ is not an integer constant
VIRTCHNL_CHECK_STRUCT_LEN(16, virtchnl_iwarp_qvlist_info);
^~~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/avf/virtchnl.h:147:53: note: in definition of macro ‘VIRTCHNL_CHECK_STRUCT_LEN’
{ virtchnl_static_assert_##X = (n)/((sizeof(struct X) == (n)) ? 1 : 0) }
^

Fix this by adding explicit padding to structures with holes.

Reported-by: <[e-mail]>
Signed-off-by: Geert Uytterhoeven <[e-mail]>
Tested-by: Andrew Bowers <[e-mail]>
Signed-off-by: Jeff Kirsher <[e-mail]>

include/linux/avf/virtchnl.h

···
 	u16 vsi_id;
 	u16 key_len;
 	u8 key[1];         /* RSS hash key, packed bytes */
+	u8 pad[1];
 };
 
 VIRTCHNL_CHECK_STRUCT_LEN(6, virtchnl_rss_key);
···
 	u16 vsi_id;
 	u16 lut_entries;
 	u8 lut[1];        /* RSS lookup table */
+	u8 pad[1];
 };
 
 VIRTCHNL_CHECK_STRUCT_LEN(6, virtchnl_rss_lut);
···
 	enum	virtchnl_action action;
 	u32	action_meta;
 	u8	field_flags;
+	u8	pad[3];
 };
 
 VIRTCHNL_CHECK_STRUCT_LEN(272, virtchnl_filter);
···
 			/* link_speed provided in Mbps */
 			u32 link_speed;
 			u8 link_status;
+			u8 pad[3];
 		} link_event_adv;
 	} event_data;
 
···
 	u16 ceq_idx;
 	u16 aeq_idx;
 	u8 itr_idx;
+	u8 pad[3];
 };
 
 VIRTCHNL_CHECK_STRUCT_LEN(12, virtchnl_iwarp_qv_info);