cake: bump to 20180504 bake

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Cake is bearing fruits of kernel upstreaming efforts.

diffserv-llt dropped. DSCP mapping paper died and no one using it.

ack-filter re-written & simplified

tc userspace & cake kmod netlink interface usage changed in non
backwards compatible way, thus this once requires tc & cake to be
in-step.  Change due to upstream requirements.

Signed-off-by: Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>

package/kernel/kmod-sched-cake/Makefile

@@ -13,9 +13,10 @@ PKG_RELEASE:=1
 
 PKG_SOURCE_PROTO:=git
 PKG_SOURCE_URL:=https://github.com/dtaht/sch_cake.git
-PKG_SOURCE_DATE:=2018-03-19
+PKG_SOURCE_DATE:=2018-05-04
-PKG_SOURCE_VERSION:=0afc1bee4e9fc5d75668cb10254ab5d2d02f0098
+PKG_SOURCE_VERSION:=e848241cda393fe1fa643156bcdbe81764bfe060
-PKG_MIRROR_HASH:=b8ac95753d05ff602282ed5a799f9c953f60decebc5720ee8f0101344a5acfc4
+PKG_MIRROR_HASH:=70fd1f79dcdf39e47957fa6684a1a41c1b50f51896781bea0d27bc9e8ff057ab
+PKG_MAINTAINER:=Kevin Darbyshire-Bryant <ldir@darbyshire-bryant.me.uk>
 
 include $(INCLUDE_DIR)/package.mk