use 4.9.x for bcm28xx/rpi boards

target/config/Config.in.kernelversion

@@ -207,7 +207,7 @@ config ADK_TARGET_KERNEL_GIT_REPO_NAME
 config ADK_TARGET_KERNEL_GIT
 	string "git version"
 	depends on ADK_TARGET_KERNEL_VERSION_GIT
-	default "rpi-4.4.y" if ADK_TARGET_BOARD_BCM28XX
+	default "rpi-4.9.y" if ADK_TARGET_BOARD_BCM28XX
 	default "6a2f2e4198eaff63ee75f6085ce9f966c47b4441" if ADK_TARGET_ARCH_LM32
 	default "1d008423ab5fd12459f53342e4d17585ec63cfe4" if ADK_TARGET_SYSTEM_KINETIS_K70
 	default "902739f3353150ac9eb69ad995098f3079d862a3" if ADK_TARGET_SYSTEM_SOLIDRUN_CLEARFOG
@@ -217,7 +217,7 @@ config ADK_TARGET_KERNEL_GIT
 config ADK_TARGET_KERNEL_GIT_VER
 	string "kernel version"
 	depends on ADK_TARGET_KERNEL_VERSION_GIT
-	default "4.4.41-1-v7+" if ADK_TARGET_BOARD_BCM28XX
+	default "4.9.10-1-v7+" if ADK_TARGET_BOARD_BCM28XX
 	default "3.14.79-1+" if ADK_TARGET_SYSTEM_SOLIDRUN_IMX6
 	default "4.4.37-1+" if ADK_TARGET_SYSTEM_BEAGLEBONE_BLACK
 	default "2.6.33" if ADK_TARGET_SYSTEM_KINETIS_K70