python3-native: Fix pip install issue due to unclean build directory
When installing python3-native sometimes pips default build
directory (which is on the host and is user dependant) is left unclean,
due to this, when python3-core is being installed it tries to use
the same directory producing an error, this explicitly removes
what the previous installation might have left behind, fixing the issue.
Signed-off-by: Alejandro Hernandez <alejandro.hernandez@linux.intel.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
