Do not describe -std=c11 etc. as experimental in c.opt help text.

I noticed that c.opt still described -std=c11 and related options as
experimental in the --help text.  This patch fixes this.

Bootstrapped with no regressions on x86_64-pc-linux-gnu.

	* c.opt (std=c11): Do not describe as experimental.
	(std=gnu11): Likewise.
	(std=iso9899:2011): Likewise.

From-SVN: r228349

gcc/c-family/ChangeLog

+2015-10-01  Joseph Myers  <joseph@codesourcery.com>
+
+	* c.opt (std=c11): Do not describe as experimental.
+	(std=gnu11): Likewise.
+	(std=iso9899:2011): Likewise.
+
 2015-09-28  Nathan Sidwell  <nathan@codesourcery.com>
 
 	* c-common.c (DEF_FUNCTION_TYPE_VAR_6): New.

gcc/c-family/c.opt

@@ -1656,7 +1656,7 @@ C++ ObjC++ Alias(std=c++1z) Undocumented
 
 std=c11
 C ObjC
-Conform to the ISO 2011 C standard (experimental and incomplete support)
+Conform to the ISO 2011 C standard
 
 std=c1x
 C ObjC Alias(std=c11)
@@ -1713,7 +1713,7 @@ C++ ObjC++ Alias(std=gnu++1z) Undocumented
 
 std=gnu11
 C ObjC
-Conform to the ISO 2011 C standard with GNU extensions (experimental and incomplete support)
+Conform to the ISO 2011 C standard with GNU extensions
 
 std=gnu1x
 C ObjC Alias(std=gnu11)
@@ -1753,7 +1753,7 @@ Deprecated in favor of -std=iso9899:1999
 
 std=iso9899:2011
 C ObjC Alias(std=c11)
-Conform to the ISO 2011 C standard (experimental and incomplete support)
+Conform to the ISO 2011 C standard
 
 traditional
 Driver