SD card: wrap Petit FatFs code in #ifdef SD.

No need to compile this when not needed and also make sure it's
nowhere used with SD card support disabled.

pff.c

@@ -37,9 +37,13 @@
   - Moved integer.h content to the end of pff_conf.h, again, to avoid
     file name conflicts.
   - Changed former integer.h content to use fixed width types (int8_t, etc).
+  - Wrapped code in #ifdef SD to compile it only when needed.
 */
 
 #include "pff.h"        /* Petit FatFs configurations and declarations */
+
+#ifdef SD
+
 #include "pff_diskio.h" /* Declarations of low level disk I/O functions */
 
 
@@ -1118,3 +1122,5 @@ FRESULT pf_readdir (
 }
 
 #endif /* _USE_DIR */
+
+#endif /* SD */

pff.h

@@ -15,6 +15,10 @@
 /----------------------------------------------------------------------------*/
 /* Changes for Teacup see pff.c. */
 
+#include "sd.h"
+
+#ifdef SD
+
 #ifndef _PFATFS
 #define _PFATFS 4004    /* Revision ID */
 
@@ -157,3 +161,5 @@ FRESULT pf_readdir (DIR* dj, FILINFO* fno);                 /* Read a directory
 #endif
 
 #endif /* _PFATFS */
+
+#endif /* SD */

pff_diskio.c

@@ -5,6 +5,8 @@
 
 #include "pff_diskio.h"
 
+#ifdef SD
+
 
 /*-----------------------------------------------------------------------*/
 /* Initialize Disk Drive                                                 */
@@ -72,3 +74,5 @@ DRESULT disk_writep (
 
     return res;
 }
+
+#endif /* SD */

pff_diskio.h

@@ -3,6 +3,10 @@
 /-----------------------------------------------------------------------*/
 /* Changes for Teacup see pff.c. */
 
+#include "sd.h"
+
+#ifdef SD
+
 #ifndef _DISKIO_DEFINED
 #define _DISKIO_DEFINED
 
@@ -41,3 +45,5 @@ DRESULT disk_writep (const BYTE* buff, DWORD sc);
 #endif
 
 #endif  /* _DISKIO_DEFINED */
+
+#endif /* SD */