hyper-v: Remove internal types from UAPI header

hyper-v: Remove internal types from UAPI header

The uuid_le mistakenly comes to be an UAPI type. Since it's luckily not used by
Hyper-V APIs, we may replace with POD types, i.e. __u8 array.

Note, previously shared uuid_be had been removed from UAPI few releases ago.
This is a continuation of that process towards removing uuid_le one.

Note, there is no ABI change!

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200422131818.23088-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>