staging:rtl8192u: Refactor enum dm_dig_alg_e - Style

staging:rtl8192u: Refactor enum dm_dig_alg_e - Style

The enumerated type dm_dig_alg_e is only used by one variable in the
code, 'dig_algorithm', a member variable of the structure dig. That
member variable was defined to be of type 'u8' thus negating any
advantage of the use of an enumerated type, (compiler type-checking).

The type of the variable 'dig_algorithm' has been change to reflect
its use of the enumeration and the enumerated type moved in the file
so that it appears before it is used in the file.

Additionally the 'typedef' has been removed to clear the checkpatch
issue with defining new types, and the type renamed to
enum dig_algorithm.

The enumerated constant DIG_ALGO_MAX has been removed from the type
since it is never used in the code.

These changes are all coding style in nature and as such 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>