staging: rtl8723bs: Use min/max macros for variable comparison

Simplify code by using min and max helper macros in place of lengthy
if/else block oriented logical evaluation and value assignment. This
issue is identified by coccicheck using the minmax.cocci file.

Signed-off-by: Deepak R Varma <drv@mailo.com>
Link: https://lore.kernel.org/r/Y2OK6fcIkH3S2/1f@qemulion


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