src/include: Fix typos

Change-Id: Ia8e6e5bd5ac2565263d81df8ca81d62436a3301f
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/38441
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

src/include/spi-generic.h

@@ -264,7 +264,7 @@ void spi_release_bus(const struct spi_slave *slave);
  *   din:	Pointer to a string of bytes that will be filled in.
  *   bytesin:	How many bytes to read.
  *
- * Note that din and dout are transferred simulataneously in a full duplex
+ * Note that din and dout are transferred simultaneously in a full duplex
  * transaction. The number of clocks within one transaction is calculated
  * as: MAX(bytesout*8, bytesin*8).
  *