staging: nvec: Avoid the use of BUG_ON

Prevent a kernel panic by avoiding the use of the BUG_ON macro.
Checkpatch detected this issue.

The BUG_ON macro is not needed as such cases shouldn't happen and they
were introduced for debugging purposes.
Signed-off-by: Laura Garcia Liebana <nevola@gmail.com>
Acked-by: Marc Dietrich <marvin24@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/nvec/nvec.c

@@ -641,11 +641,9 @@ static irqreturn_t nvec_interrupt(int irq, void *dev)
 			nvec_msg_free(nvec, nvec->rx);
 			nvec->state = 3;
 			nvec_tx_set(nvec);
-			BUG_ON(nvec->tx->size < 1);
 			to_send = nvec->tx->data[0];
 			nvec->tx->pos = 1;
 		} else if (status == (I2C_SL_IRQ)) {
-			BUG_ON(nvec->rx == NULL);
 			nvec->rx->data[1] = received;
 			nvec->rx->pos = 2;
 			nvec->state = 4;