drivers: hv: vmbus: Fix checkpatch LINE_SPACING

Fixed checkpatch warning: Missing a blank line after declarations
checkpatch(LINE_SPACING)

Signed-off-by: Matheus Castello <matheus@castello.eng.br>
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/20201115195734.8338-4-matheus@castello.eng.br


Signed-off-by: Wei Liu <wei.liu@kernel.org>