ARM: drop experimental status for hotplug and Thumb2

Both these features have been around for a long time now, and haven't
had any recent issues brought up.  So lets drop their experimental
status.

In any case, hotplugis  selected by other non-experimental options
which then cause a Kconfig warning.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/arm/Kconfig

@@ -1603,8 +1603,8 @@ config NR_CPUS
 	default "4"
 
 config HOTPLUG_CPU
-	bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
-	depends on SMP && HOTPLUG && EXPERIMENTAL
+	bool "Support for hot-pluggable CPUs"
+	depends on SMP && HOTPLUG
 	help
 	  Say Y here to experiment with turning CPUs off and on.  CPUs
 	  can be controlled through /sys/devices/system/cpu.
@@ -1645,8 +1645,8 @@ config HZ
 	default 100
 
 config THUMB2_KERNEL
-	bool "Compile the kernel in Thumb-2 mode (EXPERIMENTAL)"
-	depends on CPU_V7 && !CPU_V6 && !CPU_V6K && EXPERIMENTAL
+	bool "Compile the kernel in Thumb-2 mode"
+	depends on CPU_V7 && !CPU_V6 && !CPU_V6K
 	select AEABI
 	select ARM_ASM_UNIFIED
 	select ARM_UNWIND