rtlwifi: rtl8188ee: Convert macros that set descriptor

As a first step in the conversion, the macros that set the RX and TX
descriptors are converted to static inline routines, and the names are
changed from upper to lower case. To minimize the changes in a given
step, the input descriptor information is left as as a byte array
(u8 *), even though it should be a little-endian word array (__le32 *).
That will be changed in the next patch.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>