Makefile: unexport 'PLATFORM' and 'OS' environment variables
Some package builds may fail when environment variables are present with the
same names as make variables in a package. This is a bigger problem for
environment variables with generic names, like 'PLATFORM' and 'OS'.
'PLATFORM' is for example a problem for host-acl.
Signed-off-by: Thomas De Schampheleire <thomas.de_schampheleire@nokia.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Thomas De Schampheleire