protobuf-c: Update to 1.3.1

Switched to regular tarballs. Makes updating easier and avoids having to
autoreconf. Simplifies Makefile slightly.

Updated project URL. Some Makefile reorganization was done for consistency
with other packages.

Added parallel build for faster building.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

libs/protobuf-c/Makefile

@@ -8,25 +8,23 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=libprotobuf-c
-PKG_VERSION:=v1.3.0
+PKG_VERSION:=1.3.1
 PKG_RELEASE:=1
 
-PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.bz2
-PKG_MIRROR_HASH:=596b8cfa47d66cf4278229b780125e199bc0df08defe849654b1ffb5e52b0c03
-PKG_SOURCE_SUBDIR:=$(PKG_NAME)-$(PKG_VERSION)
-PKG_SOURCE_URL:=git://github.com/protobuf-c/protobuf-c.git
-PKG_SOURCE_PROTO:=git
-PKG_SOURCE_VERSION:=$(PKG_VERSION)
+PKG_SOURCE:=protobuf-c-$(PKG_VERSION).tar.gz
+PKG_SOURCE_URL:=https://github.com/protobuf-c/protobuf-c/releases/download/v$(PKG_VERSION)
+PKG_HASH:=51472d3a191d6d7b425e32b612e477c06f73fe23e07f6a6a839b11808e9d2267
+PKG_BUILD_DIR:=$(BUILD_DIR)/protobuf-c-$(PKG_VERSION)
+HOST_BUILD_DIR:=$(BUILD_DIR_HOST)/protobuf-c-$(PKG_VERSION)
+
+PKG_MAINTAINER:=Jacob Siverskog <jacob@teenageengineering.com>
+PKG_LICENSE:=BSD-2c
 
 PKG_BUILD_DEPENDS:=protobuf-c/host
 HOST_BUILD_DEPENDS:=protobuf/host
 
 PKG_INSTALL:=1
-PKG_FIXUP:=autoreconf
-
-PKG_LICENSE:=BSD-2c
-
-PKG_MAINTAINER:=Jacob Siverskog <jacob@teenageengineering.com>
+PKG_BUILD_PARALLEL:=1
 
 include $(INCLUDE_DIR)/package.mk
 include $(INCLUDE_DIR)/host-build.mk
@@ -35,7 +33,7 @@ define Package/libprotobuf-c
   TITLE:=Protocol Buffers library
   SECTION:=libs
   CATEGORY:=Libraries
-  URL:=http://code.google.com/p/protobuf-c/
+  URL:=https://github.com/protobuf-c/protobuf-c
 endef
 
 define Package/libprotobuf-c/description