linux: default to 4.6.4

target/config/Config.in.kernelversion

@@ -4,14 +4,9 @@
 choice
 prompt "Kernel version" if !ADK_TARGET_CHOOSE_ARCH
 depends on ADK_TARGET_OS_LINUX
-default ADK_TARGET_KERNEL_VERSION_4_6_4 if ADK_TARGET_ARCH_ARC
-default ADK_TARGET_KERNEL_VERSION_4_6_4 if ADK_TARGET_ARCH_NIOS2
-default ADK_TARGET_KERNEL_VERSION_4_6_4 if ADK_TARGET_ARCH_XTENSA
-default ADK_TARGET_KERNEL_VERSION_4_6_4 if ADK_TARGET_CPU_MIPS_MIPS32R6
-default ADK_TARGET_KERNEL_VERSION_4_6_4 if ADK_TARGET_CPU_MIPS64_MIPS64R6
 default ADK_TARGET_KERNEL_VERSION_RPI if ADK_TARGET_BOARD_BCM28XX
 default ADK_TARGET_KERNEL_VERSION_FSLC if ADK_TARGET_SYSTEM_SOLIDRUN_IMX6
-default ADK_TARGET_KERNEL_VERSION_4_4_14
+default ADK_TARGET_KERNEL_VERSION_4_6_4
 
 config ADK_TARGET_KERNEL_VERSION_GIT
 	bool "linux-git"