staging:rtl8192u: Rename types in QOS_TCLAS union - Style

Whilst none of the structures inside the qos_tclas union are used, their
names conflict with the coding standard being named in uppercase.
The names of all five have been changed to lowercase.

This is a style change, and since none of the structures are referenced,
these changes should have no impact on runtime code execution.

Signed-off-by: John Whitmore <johnfwhitmore@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>