drivers/net: remove skeleton driver
drivers/net: remove skeleton driver

os/drivers/net/skeleton.c is a skeleton for Nuttx legacy ethernet
driver and this does not work in TizenRT because it uses LwIP as a
network stack. This can confuse network driver developers. So, remove
this.

Change-Id: If8cd2ea6ec1b28654d75a3915a8bff5510c0052b
Signed-off-by: EunBong Song <1a7e7e98e070490e67aa35ab67fbf9fdda8f48ac@samsung.com>

Parkjihooni6186/TizenRT,olegartys/TizenRT,JunhwanPark/TizenRT,davidfather/TizenRT,an4967/TizenRT,shivgarg/TizenRT,yashwanth686007/TizenRTOS,lssgood/TizenRT,Samsung/TizenRT,pillip8282/TizenRT,jsdosa/TizenRT,sangwon03/TizenRT,manoharahk/TizenRT,guswns0528/TizenRT,olegartys/TizenRT,junmin-kim/TizenRT,sunghan-chang/TizenRT,heejin-kim/TizenRT,btheosam/TizenRT,sunghan-chang/TizenRT,HONGCHAEHEE/TizenRT,jeongarmy/TizenRT,shivgarg/TizenRT,sunghan-chang/TizenRT,jeongarmy/TizenRT,lokeshbv/TizenRT,HONGCHAEHEE/TizenRT,JunhwanPark/TizenRT,davidfather/TizenRT,heejin-kim/TizenRT,pillip8282/TizenRT,junmin-kim/TizenRT,dr-venkman/TizenRT,an4967/TizenRT,jeongarmy/TizenRT,JeonginKim/TizenRT,jeongarmy/TizenRT,kimusan/TizenRT,davidfather/TizenRT,jeongchanKim/TizenRT,kimusan/TizenRT,sangwon03/TizenRT,EunBongSong/TizenRT,Samsung/TizenRT,chanijjani/TizenRT,olegartys/TizenRT,pillip8282/TizenRT,JunhwanPark/TizenRT,Parkjihooni6186/TizenRT,jeongchanKim/TizenRT,HONGCHAEHEE/TizenRT,Parkjihooni6186/TizenRT,davidfather/TizenRT,dr-venkman/TizenRT,pillip8282/TizenRT,chanijjani/TizenRT,dr-venkman/TizenRT,EunBongSong/TizenRT,lssgood/TizenRT,manoharahk/TizenRT,jeongchanKim/TizenRT,Samsung/TizenRT,JeongJunSik/TizenRT,shivgarg/TizenRT,youngeunpark/TizenRT,JeongJunSik/TizenRT,an4967/TizenRT,btheosam/TizenRT,pillip8282/TizenRT,jsdosa/TizenRT,lssgood/TizenRT,dr-venkman/TizenRT,jsdosa/TizenRT,kimusan/TizenRT,an4967/TizenRT,junmin-kim/TizenRT,yashwanth686007/TizenRTOS,lokeshbv/TizenRT,sunghan-chang/TizenRT,youngeunpark/TizenRT,olegartys/TizenRT,JeonginKim/TizenRT,JeongJunSik/TizenRT,lokeshbv/TizenRT,btheosam/TizenRT,guswns0528/TizenRT,jsdosa/TizenRT,sunghan-chang/TizenRT,lssgood/TizenRT,JunhwanPark/TizenRT,heejin-kim/TizenRT,jeongchanKim/TizenRT,sunghan-chang/TizenRT,JeonginKim/TizenRT,EunBongSong/TizenRT,olegartys/TizenRT,HONGCHAEHEE/TizenRT,chanijjani/TizenRT,jeongchanKim/TizenRT,jeongchanKim/TizenRT,JunhwanPark/TizenRT,jeongchanKim/TizenRT,jeongarmy/TizenRT,guswns0528/TizenRT,an4967/TizenRT,HONGCHAEHEE/TizenRT,chanijjani/TizenRT,Samsung/TizenRT,JeongJunSik/TizenRT,sunghan-chang/TizenRT,an4967/TizenRT,EunBongSong/TizenRT,Parkjihooni6186/TizenRT,shivgarg/TizenRT,EunBongSong/TizenRT,lokeshbv/TizenRT,jsdosa/TizenRT,chanijjani/TizenRT,lokeshbv/TizenRT,chanijjani/TizenRT,pillip8282/TizenRT,yashwanth686007/TizenRTOS,btheosam/TizenRT,btheosam/TizenRT,heejin-kim/TizenRT,manoharahk/TizenRT,pillip8282/TizenRT,davidfather/TizenRT,kimusan/TizenRT,yashwanth686007/TizenRTOS,btheosam/TizenRT,youngeunpark/TizenRT,youngeunpark/TizenRT,shivgarg/TizenRT,lokeshbv/TizenRT,jeongarmy/TizenRT,Parkjihooni6186/TizenRT,manoharahk/TizenRT,heejin-kim/TizenRT,guswns0528/TizenRT,davidfather/TizenRT,Parkjihooni6186/TizenRT,sangwon03/TizenRT,an4967/TizenRT,JeongJunSik/TizenRT,HONGCHAEHEE/TizenRT,Samsung/TizenRT,lssgood/TizenRT,junmin-kim/TizenRT,jsdosa/TizenRT,JeonginKim/TizenRT,davidfather/TizenRT,yashwanth686007/TizenRTOS,JeongJunSik/TizenRT,junmin-kim/TizenRT,JeonginKim/TizenRT,youngeunpark/TizenRT,yashwanth686007/TizenRTOS,dr-venkman/TizenRT,chanijjani/TizenRT,junmin-kim/TizenRT,jeongarmy/TizenRT,heejin-kim/TizenRT,guswns0528/TizenRT,manoharahk/TizenRT,junmin-kim/TizenRT,EunBongSong/TizenRT,shivgarg/TizenRT,sangwon03/TizenRT,dr-venkman/TizenRT,JeonginKim/TizenRT,sangwon03/TizenRT,kimusan/TizenRT,Samsung/TizenRT,JunhwanPark/TizenRT,sangwon03/TizenRT,manoharahk/TizenRT,Samsung/TizenRT,youngeunpark/TizenRT,kimusan/TizenRT,olegartys/TizenRT,jsdosa/TizenRT,lssgood/TizenRT