vt: add documentation for new boot/sysfs options

Add description to Documentation/kernel-parameters.txt on new options
default_blue, default_grn, default_red, and default_utf8.
Signed-off-by: NAntonino Daplas <adaplas@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Documentation/kernel-parameters.txt

@@ -496,6 +496,30 @@ and is between 256 and 4096 characters. It is defined in the file
 			Format: <area>[,<node>]
 			See also Documentation/networking/decnet.txt.
 
+	default_blu=	[VT]
+			Format: <blue0>,<blue1>,<blue2>,...,<blue15>
+			Change the default blue palette of the console.
+			This is a 16-member array composed of values
+			ranging from 0-255.
+
+	default_grn=	[VT]
+			Format: <green0>,<green1>,<green2>,...,<green15>
+			Change the default green palette of the console.
+			This is a 16-member array composed of values
+			ranging from 0-255.
+
+	default_red=	[VT]
+			Format: <red0>,<red1>,<red2>,...,<red15>
+			Change the default red palette of the console.
+			This is a 16-member array composed of values
+			ranging from 0-255.
+
+	default_utf8=   [VT]
+			Format=<0|1>
+			Set system-wide default UTF-8 mode for all tty's.
+			Default is 0 and by setting to 1, it enables UTF-8
+			mode for all newly opened or allocated terminals.
+
 	dhash_entries=	[KNL]
 			Set number of hash buckets for dentry cache.