libvpx: Makefile polishing

- Remove PKG_REV
- Reorder things to be more sync with other Makefiles
- Add PKG_BUILD_PARALLEL

Signed-off-by: Josef Schlehofer <pepe.schlehofer@gmail.com>

libs/libvpx/Makefile

@@ -12,18 +12,17 @@ PKG_NAME:=libvpx
 PKG_VERSION:=1.8.2
 PKG_RELEASE:=1
 
-PKG_REV:=v$(PKG_VERSION)
-PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION)-$(PKG_REV).tar.gz
-PKG_MIRROR_HASH:=51e871a928fe98f14fd08285cb9b64c0d540b36b630ee7d47bc464e909366db7
-PKG_SOURCE_URL:=https://chromium.googlesource.com/webm/libvpx
 PKG_SOURCE_PROTO:=git
-PKG_SOURCE_VERSION:=$(PKG_REV)
-PKG_SOURCE_SUBDIR:=$(PKG_NAME)-$(PKG_VERSION)
-PKG_CPE_ID:=cpe:/a:john_koleszar:libvpx
+PKG_SOURCE_URL:=https://chromium.googlesource.com/webm/libvpx
+PKG_MIRROR_HASH:=51e871a928fe98f14fd08285cb9b64c0d540b36b630ee7d47bc464e909366db7
+PKG_SOURCE_VERSION:=v$(PKG_VERSION)
+PKG_SOURCE:=$(PKG_NAME)-$(PKG_SOURCE_VERSION).tar.gz
 
 PKG_MAINTAINER:=Luiz Angelo Daros de Luca <luizluca@gmail.com>
 PKG_LICENSE:=BSD-3-Clause
 PKG_LICENSE_FILES:=LICENSE
+PKG_CPE_ID:=cpe:/a:john_koleszar:libvpx
+PKG_BUILD_PARALLEL:=1
 
 PKG_ABI_VERSION:=$(subst $(space),.,$(wordlist 1, 2, $(subst .,$(space),$(PKG_VERSION))))