include/linux/printk.h lib/hexdump.c: neatening and add CONFIG_PRINTK guard

- Move prototypes and align arguments.

- Add CONFIG_PRINTK guard for print_hex functions

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

lib/hexdump.c

@@ -154,6 +154,7 @@ nil:
 }
 EXPORT_SYMBOL(hex_dump_to_buffer);
 
+#ifdef CONFIG_PRINTK
 /**
  * print_hex_dump - print a text hex dump to syslog for a binary blob of data
  * @level: kernel log level (e.g. KERN_DEBUG)
@@ -238,3 +239,4 @@ void print_hex_dump_bytes(const char *prefix_str, int prefix_type,
 		       buf, len, true);
 }
 EXPORT_SYMBOL(print_hex_dump_bytes);
+#endif