Added log level configuration to Kconfig.

Kconfig

@@ -35,4 +35,34 @@ menu "KTag SystemK"
         help
             Value of audio volume representing the minimum volume possible for this device.
 
+    config SYSTEMK_LOG_LEVEL
+        int
+        default 0 if SYSTEMK_LOG_LEVEL_NONE
+        default 1 if SYSTEMK_LOG_LEVEL_ERROR
+        default 2 if SYSTEMK_LOG_LEVEL_WARN
+        default 3 if SYSTEMK_LOG_LEVEL_INFO
+        default 4 if SYSTEMK_LOG_LEVEL_DEBUG
+        default 5 if SYSTEMK_LOG_LEVEL_VERBOSE
+
+    choice SYSTEMK_LOG_LEVEL_CHOICE
+        bool "SystemK maximum log level"
+        default SYSTEMK_LOG_LEVEL_VERBOSE
+        help
+            Set the maximum compiled log level for SystemK.
+            Messages at higher levels will be removed at compile time.
+
+        config SYSTEMK_LOG_LEVEL_NONE
+            bool "No output"
+        config SYSTEMK_LOG_LEVEL_ERROR
+            bool "Error"
+        config SYSTEMK_LOG_LEVEL_WARN
+            bool "Warning"
+        config SYSTEMK_LOG_LEVEL_INFO
+            bool "Info"
+        config SYSTEMK_LOG_LEVEL_DEBUG
+            bool "Debug"
+        config SYSTEMK_LOG_LEVEL_VERBOSE
+            bool "Verbose"
+    endchoice
+
 endmenu