Rename programmer registration functions

register_programmer suggests that we register a programmer. However,
that function registers a master for a given bus type, and a programmer
may support multiple masters (e.g. SPI, FWH). Rename a few other
functions to be more consistent.

Signed-off-by: Carl-Daniel Hailfinger <c-d.hailfinger.devel.2006@gmx.net>
Acked-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>


git-svn-id: svn://flashrom.org/flashrom/trunk@1831 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1