staging: pi433: rf69.c style fix - space before asterisk

This patch fixes the following checkpatch.pl error:

ERROR: "(foo*)" should be "(foo *)"

in rf69.c file as requested by TODO file.

Additionally some style warnings remain valid here and could be fixed by
another patch.
Signed-off-by: Marcin Ciupak <marcin.s.ciupak@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/pi433/rf69.c

@@ -919,7 +919,7 @@ int rf69_set_fifo_threshold(struct spi_device *spi, u8 threshold)
 		return retval;
 
 	// access the fifo to activate new threshold
-	return rf69_read_fifo (spi, (u8*) &retval, 1); // retval used as buffer
+	return rf69_read_fifo(spi, (u8 *)&retval, 1); // retval used as buffer
 }
 
 int rf69_set_dagc(struct spi_device *spi, enum dagc dagc)