Add IOCTL command names to driver library logging

Currently the driver library will log IOCTL commands as hexadecimal
values, which makes it hard to know what command is being logged unless
you know the command values. To make this easier, the driver library
will now translate the command values into their respective names when
logging.

Change-Id: I7ef2f411b0261ea7819c1a7a6825422859031a25
Signed-off-by: Mikael Olsson <mikael.olsson@arm.com>