fpga: Remove extern prototypes from .h

This problem is reported by checkpatch.pl
Warnings:
CHECK: extern prototypes should be avoided in .h files

Signed-off-by: Michal Simek <michal.simek@xilinx.com>

include/fpga.h

@@ -49,18 +49,18 @@ typedef enum {
 } bitstream_type;
 
 /* root function definitions */
-extern void fpga_init(void);
-extern int fpga_add(fpga_type devtype, void *desc);
-extern int fpga_count(void);
-extern int fpga_load(int devnum, const void *buf, size_t bsize,
-		     bitstream_type bstype);
-extern int fpga_fsload(int devnum, const void *buf, size_t size,
-		       fpga_fs_info *fpga_fsinfo);
-extern int fpga_loadbitstream(int devnum, char *fpgadata, size_t size,
-			      bitstream_type bstype);
-extern int fpga_dump(int devnum, const void *buf, size_t bsize);
-extern int fpga_info(int devnum);
-extern const fpga_desc *const fpga_validate(int devnum, const void *buf,
-					    size_t bsize, char *fn);
+void fpga_init(void);
+int fpga_add(fpga_type devtype, void *desc);
+int fpga_count(void);
+int fpga_load(int devnum, const void *buf, size_t bsize,
+	      bitstream_type bstype);
+int fpga_fsload(int devnum, const void *buf, size_t size,
+		fpga_fs_info *fpga_fsinfo);
+int fpga_loadbitstream(int devnum, char *fpgadata, size_t size,
+		       bitstream_type bstype);
+int fpga_dump(int devnum, const void *buf, size_t bsize);
+int fpga_info(int devnum);
+const fpga_desc *const fpga_validate(int devnum, const void *buf,
+				     size_t bsize, char *fn);
 
 #endif	/* _FPGA_H_ */