misc: bcm-vk: avoid -Wflex-array-member-not-at-end warning

Fix the following warning by removing unused flex-array member
`data` in `struct bcm_vk_peer_log`:

drivers/misc/bcm-vk/bcm_vk.h:415:32: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]

Signed-off-by: Gustavo A. R. Silva <[e-mail]>
Acked-by: Scott Branden <[e-mail]>
Link: https://lore.kernel.org/r/Z9Nd4AmgrQDiK1Gn@kspp
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/misc/bcm-vk/bcm_vk.h

···
 	u32 wr_idx;
 	u32 buf_size;
 	u32 mask;
-	char data[];
 };
 
 /* max buf size allowed */