lib/: make RUNTIME_TESTS a menuconfig to ease disabling it all

lib/: make RUNTIME_TESTS a menuconfig to ease disabling it all

No need to get into the submenu to disable all related config entries.

This makes it easier to disable all RUNTIME_TESTS config options without
entering the submenu.  It will also enable one to see that en/dis-abled
state from the outside menu.

This is only intended to change menuconfig UI, not change the config
dependencies.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Vincent Legoll <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Byungchul Park <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: "Paul E. McKenney" <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Geert Uytterhoeven <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: "Luis R. Rodriguez" <[email protected]>
Cc: Nicholas Piggin <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>