1. Paris is a world capital in a country that generally believed itself not at war on its own territory. Combat breaking out in such a capital is big news. When capitals fall, regimes fall. Baga is a remote border town that is not even the capital of its local state. It has come under attack within the past two years and it's likely to happen again during the next two years as things go.
2. Boko Haram is a significant military force that at least sort of fits within the standard framework of how people go to war in the modern age. The irregulars attacking in Paris are an example of a systemic threat to the Westphalian system that has undergirded how nations interact with each other since the peace of Westphalia in 1648. If Westphalia goes, a lot of things change. If Boko Haram takes even a province or two, nothing systemic changes.
3. Nigeria's rulers have decided that it is in their interest to minimize the tragedy of Baga. France's rulers have decided that it is in their interests to play up the tragedy of Paris. The rest of the world's leadership rightfully take cues from the leader of the country in which the attack has taken place.
4. There is a political affinity between France's governing party (socialist) and the marxists that put out Charlie Hebdo. There is a political rivalry between the muslim north (where Baga is) and the christian south (where the current government is drawn from). This naturally leads to different treatment. While it's unfortunate, race has nothing to do with it in either case.