init/Kconfig: Hide printk log config if CONFIG_PRINTK=n

The buffers sized by CONFIG_LOG_BUF_SHIFT and
CONFIG_LOG_CPU_MAX_BUF_SHIFT do not exist if CONFIG_PRINTK=n, so don't
ask about their size at all.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Cc: stable <stable@vger.kernel.org>

init/Kconfig

@@ -811,6 +811,7 @@ config LOG_BUF_SHIFT
 	int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
 	range 12 21
 	default 17
+	depends on PRINTK
 	help
 	  Select the minimal kernel log buffer size as a power of 2.
 	  The final size is affected by LOG_CPU_MAX_BUF_SHIFT config
@@ -830,6 +831,7 @@ config LOG_CPU_MAX_BUF_SHIFT
 	range 0 21
 	default 12 if !BASE_SMALL
 	default 0 if BASE_SMALL
+	depends on PRINTK
 	help
 	  This option allows to increase the default ring buffer size
 	  according to the number of CPUs. The value defines the contribution