staging: rts5208: remove parentheses pair in sd.c

I had missed a single parentheses pair in the commit for sd.c.
This commit removes the pair I missed.

Signed-off-by: Benjamin Philip <benjamin.philip495@gmail.com>
Link: https://lore.kernel.org/r/4a56facd2c04a321b091d3b7dbea87168e8ddd6e.1632209460.git.benjamin.philip495@gmail.com


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