fix build flags

linux/linux.mk

@@ -177,7 +177,7 @@ endif
 # sanitize the arguments passed from user space in registers.
 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82435
 ifeq ($(BR2_TOOLCHAIN_GCC_AT_LEAST_8),y)
-LINUX_MAKE_ENV += KCFLAGS="-Wno-attribute-alias -Wno-address -Wno-array-compare -Wno-stringop-overread -Wno-misleading-indentation -Wno-dangling-pointer -Wno-enum-int-mismatch"
+LINUX_MAKE_ENV += KCFLAGS="-Wno-attribute-alias -Wno-address -Wno-array-compare -Wno-stringop-overread -Wno-misleading-indentation -Wno-dangling-pointer -Wno-enum-int-mismatch -Wno-declaration-after-statement -Wno-deprecated-declarations -Wno-int-in-bool-context"
 endif
 
 ifeq ($(BR2_LINUX_KERNEL_DTB_OVERLAY_SUPPORT),y)