libvpx: bump to 1.8.1

Signed-off-by: Luiz Angelo Daros de Luca <luizluca@gmail.com>

libs/libvpx/Makefile

@@ -9,12 +9,12 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=libvpx
-PKG_VERSION:=1.8.0
+PKG_VERSION:=1.8.1
 PKG_RELEASE:=1
 
 PKG_REV:=v$(PKG_VERSION)
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION)-$(PKG_REV).tar.gz
-PKG_MIRROR_HASH:=caf53ffff549fefb14d8d054db014c6394e1955d199b80dc985ef6098bd4213d
+PKG_MIRROR_HASH:=6703842a870727b621a82efe5b2ff6f5553d41f7b0905dd4fde1f8bdf062d6ea
 PKG_SOURCE_URL:=https://chromium.googlesource.com/webm/libvpx
 PKG_SOURCE_PROTO:=git
 PKG_SOURCE_VERSION:=$(PKG_REV)