x86: make early printk selectable on 64-bit as well

Enable CONFIG_EMBEDDED to select CONFIG_EARLY_PRINTK on 64-bit as well.

saves ~2K:

   text    data     bss     dec     hex filename
   7290283 3672091 1907848 12870222         c4624e vmlinux.before
   7288373 3671795 1907848 12868016         c459b0 vmlinux.after

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index a7283c9..ff356b2 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -194,6 +194,9 @@
 static inline int log_buf_copy(char *dest, int idx, int len) { return 0; }
 #endif
 
+extern void __attribute__((format(printf, 1, 2)))
+	early_printk(const char *fmt, ...);
+
 unsigned long int_sqrt(unsigned long);
 
 extern int printk_ratelimit(void);