Staging: rts_pstor: dont cast void* from kmalloc()

 Casting (void *) value returned by kmalloc is useless
 as mentioned in Documentation/CodingStyle, Chap 14.

 The semantic patch that makes this output is available
 in scripts/coccinelle/api/alloc/drop_kmalloc_cast.cocci.

 More information about semantic patching is available at
 http://coccinelle.lip6.fr/Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/rts_pstor/spi.c

@@ -463,7 +463,7 @@ int spi_read_flash_id(struct scsi_cmnd *srb, struct rtsx_chip *chip)
 	}
 
 	if (len) {
-		buf = (u8 *)kmalloc(len, GFP_KERNEL);
+		buf = kmalloc(len, GFP_KERNEL);
 		if (!buf)
 			TRACE_RET(chip, STATUS_ERROR);