python-packages: Clean up build variables

* Rename PYTHON3_PKG_SETUP_VARS to PYTHON3_PKG_BUILD_VARS, and
  PYTHON3_PKG_SETUP_DIR to PYTHON3_PKG_BUILD_PATH

  The new variable names emphasize that these values apply to the new
  build process.

* Remove PYTHON3_PKG_SETUP_ARGS set to the empty string

  These were set to override the default arguments in the old build
  process and not applicable to the new build process.

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

lang/python/python-crcmod/Makefile

@@ -5,7 +5,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=python-crcmod
 PKG_VERSION:=1.7
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PYPI_NAME:=crcmod
 PKG_HASH:=dc7051a0db5f2bd48665a990d3ec1cc305a466a77358ca4492826f41f283601e
@@ -13,8 +13,6 @@ PKG_HASH:=dc7051a0db5f2bd48665a990d3ec1cc305a466a77358ca4492826f41f283601e
 PKG_LICENSE:=MIT
 PKG_MAINTAINER:=David Bauer <mail@david-bauer.net>
 
-PYTHON3_PKG_SETUP_ARGS:=
-
 include ../pypi.mk
 include $(INCLUDE_DIR)/package.mk
 include ../python3-package.mk