loadable_sample: fix wrong syntax of Kconfig
loadable_sample: fix wrong syntax of Kconfig

1. Remove default value in choice
  Configs which are in choice should not have default syntax.

make[1]: Leaving directory '/root/tizenrt/loadable_apps'
/root/tizenrt/loadable_apps/loadable_sample/Kconfig:73:warning: defaults for choice values not supported
/root/tizenrt/loadable_apps/loadable_sample/Kconfig:82:warning: defaults for choice values not supported
/root/tizenrt/loadable_apps/loadable_sample/Kconfig:89:warning: defaults for choice values not supported

2. Relocate timer againg sub-configs
  When the timer againg config is enabled, sub-configs are shown in choice syntax.
  It looks much strange. Let's move them out from the choice.

Signed-off-by: sunghan-chang <c954e25285721d8faa8b1a5c1ae2ef5a35338d32@samsung.com>

junmin-kim/TizenRT,jeongchanKim/TizenRT,jsdosa/TizenRT,jsdosa/TizenRT,pillip8282/TizenRT,Samsung/TizenRT,jeongarmy/TizenRT,Samsung/TizenRT,jsdosa/TizenRT,jsdosa/TizenRT,junmin-kim/TizenRT,jsdosa/TizenRT,Samsung/TizenRT,Samsung/TizenRT,jeongarmy/TizenRT,jeongchanKim/TizenRT,an4967/TizenRT,jeongchanKim/TizenRT,Samsung/TizenRT,an4967/TizenRT,junmin-kim/TizenRT,pillip8282/TizenRT,jeongarmy/TizenRT,an4967/TizenRT,jsdosa/TizenRT,sunghan-chang/TizenRT,an4967/TizenRT,pillip8282/TizenRT,jsdosa/TizenRT,an4967/TizenRT,pillip8282/TizenRT,jeongarmy/TizenRT,junmin-kim/TizenRT,jeongchanKim/TizenRT,jeongchanKim/TizenRT,sunghan-chang/TizenRT,junmin-kim/TizenRT,sunghan-chang/TizenRT,pillip8282/TizenRT,Samsung/TizenRT,jeongchanKim/TizenRT,Samsung/TizenRT,an4967/TizenRT,an4967/TizenRT,pillip8282/TizenRT,pillip8282/TizenRT,sunghan-chang/TizenRT,junmin-kim/TizenRT,jeongchanKim/TizenRT,junmin-kim/TizenRT,sunghan-chang/TizenRT,jeongarmy/TizenRT,sunghan-chang/TizenRT,jeongarmy/TizenRT,sunghan-chang/TizenRT,jeongarmy/TizenRT