staging: rtl8723bs: replace underutilized struct by array variable

For structure iqk_matrix_regs_setting, only the "Value" member variable
is utilized whereas the other struct members are only declared but not
utilised. Replace the struct declaration and implementation by an
equivalent variable similar to the only used struct member variable.
While in there, update the macro mixed case names to uppercase style.
The resultant code is simpler and is easy to maintain.

Suggested-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Deepak R Varma <drv@mailo.com>
Link: https://lore.kernel.org/r/Y2ZF6O1KU3zZ6r3C@qemulion


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>