sfc: Fix some formatting errors reported by checkpatch

Fix the following errors and warnings:

ERROR: trailing whitespace
ERROR: spaces required around that '=' (ctx:VxV)
WARNING: please, no space before tabs
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>

drivers/net/ethernet/sfc/selftest.c

@@ -445,7 +445,7 @@ static int efx_end_loopback(struct efx_tx_queue *tx_queue,
 
 	/* Count the number of tx completions, and decrement the refcnt. Any
 	 * skbs not already completed will be free'd when the queue is flushed */
-	for (i=0; i < state->packet_count; i++) {
+	for (i = 0; i < state->packet_count; i++) {
 		skb = state->skbs[i];
 		if (skb && !skb_shared(skb))
 			++tx_done;

drivers/net/ethernet/sfc/spi.h

@@ -68,7 +68,7 @@ static inline bool efx_spi_present(const struct efx_spi_device *spi)
 
 int falcon_spi_cmd(struct efx_nic *efx,
 		   const struct efx_spi_device *spi, unsigned int command,
-		   int address, const void* in, void *out, size_t len);
+		   int address, const void *in, void *out, size_t len);
 int falcon_spi_wait_write(struct efx_nic *efx,
 			  const struct efx_spi_device *spi);
 int falcon_spi_read(struct efx_nic *efx,