staging: mt7621-pinctrl: avoid space after if condition

Adding spaces between if condition and parenthesis are not
needed at all and checkpatch script complains about them.
Fix one in driver code.

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>