config: kernel: remove KERNEL_LXC_MISC

Kernel features are neutral.  The two cascaded features can also be
useful for other container related tools

It's also less error-prone if only kconfig symbols from the kernel are
prefixed KERNEL_

Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>

config/Config-kernel.in

@@ -623,16 +623,6 @@ if KERNEL_NAMESPACES
 
 endif
 
-#
-# LXC related symbols
-#
-
-config KERNEL_LXC_MISC
-	bool "Enable miscellaneous LXC related options"
-	default y if !SMALL_FLASH
-
-if KERNEL_LXC_MISC
-
 config KERNEL_DEVPTS_MULTIPLE_INSTANCES
 	bool "Support multiple instances of devpts"
 	default y
@@ -657,7 +647,6 @@ if KERNEL_LXC_MISC
 	  and can be mounted somewhere if you want to do filesystem
 	  operations on message queues.
 
-endif
 
 config KERNEL_SECCOMP_FILTER
 	bool