sparc64: Fix build warnings in piggyback_64.c

This patch fixes the following build warnings:
arch/sparc/boot/piggyback_64.c: In function 'main':
arch/sparc/boot/piggyback_64.c:44: warning: 'end' may be used uninitialized in this function
arch/sparc/boot/piggyback_64.c:44: warning: 'start' may be used uninitialized in this function

Signed-off-by: Julian Calaby <julian.calaby@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc/boot/piggyback_64.c

@@ -46,6 +46,7 @@ int main(int argc,char **argv)
 	struct stat s;
 	int image, tail;
 
+	start = end = 0;
 	if (stat (argv[3], &s) < 0) die (argv[3]);
 	map = fopen (argv[2], "r");
 	if (!map) die(argv[2]);