[build]: Add missing 'rm -rf' to component Makefiles for clean rebuild (

#3028)

* src/iproute2/Makefile
* src/python3/Makefile

These Makefiles do not properly clean out the src build subdirectory
prior to downloading the source code contents. This causes an error
during a rebuild following a 'make clean'.

Signed-off-by: Greg Paussa <greg.paussa@broadcom.com>

src/iproute2/Makefile

@@ -8,6 +8,9 @@ IPROUTE2_VERSION_FULL = $(IPROUTE2_VERSION)-1
 MAIN_TARGET = iproute2_$(IPROUTE2_VERSION_FULL)_amd64.deb
 
 $(addprefix $(DEST)/, $(MAIN_TARGET)): $(DEST)/% :
+	# Remove any stale files
+	rm -rf iproute2-$(IPROUTE2_VERSION)
+
 	wget -O iproute2_$(IPROUTE2_VERSION).orig.tar.xz -N "https://sonicstorage.blob.core.windows.net/packages/iproute2_4.9.0.orig.tar.xz?sv=2015-04-05&sr=b&sig=9nvybd1xkXyRQbaG6Fy6wBazPA8IbZV0AO41GWXPEP8%3D&se=2154-10-23T11%3A59%3A00Z&sp=r"
 	wget -O iproute2_$(IPROUTE2_VERSION_FULL).dsc -N "https://sonicstorage.blob.core.windows.net/packages/iproute2_4.9.0-1.dsc?sv=2015-04-05&sr=b&sig=m6FcMH9dOh8ggipBgOsONiXvDxoi6bfUO%2BxvidsMNMQ%3D&se=2154-10-23T11%3A59%3A53Z&sp=r"
 	wget -O iproute2_$(IPROUTE2_VERSION_FULL).debian.tar.xz -N "https://sonicstorage.blob.core.windows.net/packages/iproute2_4.9.0-1.debian.tar.xz?sv=2015-04-05&sr=b&sig=U5NFuwG5C3vZXlUUNvoPMnKDtMKk66zbweA9rQYbEVY%3D&se=2154-10-23T12%3A00%3A15Z&sp=r"

src/python3/Makefile

@@ -15,6 +15,9 @@ DERIVED_TARGETS = lib$(PYTHON_PNAME)-stdlib_$(PYTHON_VER)-$(PYTHON_DEB_VER)_amd6
 				  #$(PYTHON_PNAME)-dev_$(PYTHON_VER)-$(PYTHON_DEB_VER)_amd64.deb
 
 $(addprefix $(DEST)/, $(MAIN_TARGET)): $(DEST)/% :
+	# Remove any stale files
+	rm -rf $(PYTHON_PNAME)-$(PYTHON_VER)
+
 	## Obtaining the python3
 	wget 'https://sonicstorage.blob.core.windows.net/packages/$(PYTHON_PNAME)_$(PYTHON_VER).orig.tar.xz?sv=2015-04-05&sr=b&sig=d42Wh1CA9NZvlskhW4fpWcHVgc7N3IKhdFzyeO2zbRA%3D&se=2027-02-02T01%3A00%3A57Z&sp=r' -O $(PYTHON_PNAME)_$(PYTHON_VER).orig.tar.xz
 	wget 'https://sonicstorage.blob.core.windows.net/packages/$(PYTHON_PNAME)_$(PYTHON_VER)-$(PYTHON_DEB_VER).debian.tar.xz?sv=2015-04-05&sr=b&sig=KLX9pMJ3zpQvGBo6ZjzoZXgooMJRUUwMx8ZaTJtywK0%3D&se=2027-02-02T00%3A59%3A34Z&sp=r' -O $(PYTHON_PNAME)_$(PYTHON_VER)-$(PYTHON_DEB_VER).debian.tar.xz