python-packages: Clean up Makefiles

This removes:

* Python 3 variants (VARIANT:=python3)

* "for Python3" from package titles

* Package selection condition from package dependencies, e.g.
  +PACKAGE_python3-six:python3-light replaced with +python3-light

* "Default" package information sections, e.g.
  Package/python-six/Default removed and package details merged into
  Package/python3-six

* "(Variant for Python3)" from package descriptions

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

lang/python/python-pycparser/Makefile

@@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
 
 PKG_NAME:=python-pycparser
 PKG_VERSION:=2.20
-PKG_RELEASE:=1
+PKG_RELEASE:=2
 
 PYPI_NAME:=pycparser
 PKG_HASH:=2d475327684562c3a96cc71adf7dc8c4f0565175cf86b6d7a404ff4c771f15f0
@@ -24,28 +24,21 @@ include ../pypi.mk
 include $(INCLUDE_DIR)/package.mk
 include ../python3-package.mk
 
-define Package/python-pycparser/Default
+define Package/python3-pycparser
   SECTION:=lang
   CATEGORY:=Languages
   SUBMENU:=Python
   TITLE:=C parser in Python
   URL:=https://github.com/eliben/pycparser
-endef
-
-define Package/python3-pycparser
-$(call Package/python-pycparser/Default)
   DEPENDS:= \
-      +PACKAGE_python3-pycparser:python3-light \
-      +PACKAGE_python3-pycparser:python3-ply
-  VARIANT:=python3
+      +python3-light \
+      +python3-ply
 endef
 
 define Package/python3-pycparser/description
 pycparser is a parser for the C language, written in pure Python. It is a
 module designed to be easily integrated into applications that need to parse
 C source code.
-.
-(Variant for Python3)
 endef
 
 $(eval $(call Py3Package,python3-pycparser))