[POWERPC] bootwrapper: Add a fatal error helper

Add a macro fatal that calls printf then exit.  User must include stdio.h.

Typically replaces 3 lines with 1, although I added back some whitespace.

Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/powerpc/boot/of.c

@@ -212,10 +212,9 @@ static void *of_vmlinux_alloc(unsigned long size)
 {
 	void *p = malloc(size);
 
-	if (!p) {
-		printf("Can't allocate memory for kernel image!\n\r");
-		exit();
-	}
+	if (!p)
+		fatal("Can't allocate memory for kernel image!\n\r");
+
 	return p;
 }