mt76: update to the latest openwrt-19.07 version

8a78567 mt76: fix compilation warning in mt76_eeprom_override()

Signed-off-by: David Bauer <mail@david-bauer.net>

package/kernel/mt76/Makefile

@@ -8,9 +8,9 @@ PKG_LICENSE_FILES:=
 
 PKG_SOURCE_URL:=https://github.com/openwrt/mt76
 PKG_SOURCE_PROTO:=git
-PKG_SOURCE_DATE:=2020-01-03
-PKG_SOURCE_VERSION:=330e8324e5eca50cda36ccc9248e704b70d5e6a3
-PKG_MIRROR_HASH:=fb06aa9913cc4acf577edc7e15e475c384dcc074b7905499d172892c745001c9
+PKG_SOURCE_DATE:=2020-01-04
+PKG_SOURCE_VERSION:=8a78567983a16869b77a0254b4917027df4a7ad9
+PKG_MIRROR_HASH:=0cc48bc7093b99dc7f43a5a83a3a00d205709326f529b91b0b14fe0d89cb783d
 
 PKG_MAINTAINER:=Felix Fietkau <nbd@nbd.name>
 PKG_BUILD_PARALLEL:=1