staging: rts5208: remove not used typedef in rtsx_sys.h

This patch fixes the following checkpatch.pl warning in rtsx_sys.h:
WARNING: do not add new typedefs
Signed-off-by: NSergio Paracuellos <sergio.paracuellos@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/rts5208/rtsx_sys.h

@@ -28,8 +28,6 @@
 #include "rtsx_chip.h"
 #include "rtsx_card.h"
 
-typedef dma_addr_t ULONG_PTR;
-
 static inline void rtsx_exclusive_enter_ss(struct rtsx_chip *chip)
 {
 	struct rtsx_dev *dev = chip->rtsx;