staging:rtl8192u: Rename EEPROM_TxPwIndex_OFDM_24G_V1 - STYLE

Rename the constant EEPROM_TxPwIndex_OFDM_24G_V1 to
EEPROM_TX_PW_INDEX_OFDM_24G_V1, this change clears the checkpatch
issue with CamelCase naming.

This is a coding style change which 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>