1) fix_tools_exports.pl need only be run on Windows hosts; was run unnecessarily on Linux too.
2) Need to export modload.pm on Linux as well as Windows hosts.
By default, .mmp files that include FEATUREVARIANT will generate binaries for
both "normal", non-binary variant, build configurations and binary variant
build configurations.
In order to ensure that only invariant binaries are created for invariant
build configurations, and variant binaries for variant build configurations,
the optional setting FEATUREVARIANTSAFE can be used. FEATUREVARIANTSAFE can be
set via an os_properties.xml file and, when set, variant binaries will no
longer be created for invariant build configurations.