Add OpenPLi 2.1 OE as build environment (for dm800)
common.mak: Global changes for various other projects.
k8055: rework for better coding practises.
tsl2550: fix invalid data fetched from device too quickly and
fixed another bug where  "true/false" was returned from a "double" function.
tsl2550: cosmetics: change order of methods to reflect code flow.
tsl2550: generic cosmetics
Changes to be able to use an other version of libusb, so
iocd can be built for dm800 (OpenPLi 2.1).