gpu: pvr: remove CommonBridgeInit()

gpu: pvr: remove CommonBridgeInit()

By dynamically assigning the function names in the BridgeDispatchTable, an
extra layer of potential errors (when CommonBridgeInit or
SetSGXDispatchTableEntry is not in full sync with the switch statement in
bridged_ioctl()) is removed.

/proc/pvr/bridge_stats now no longer shows IOCTL names and the function
they are supposed to be mapped to. It now shows actual IOCTL numbers, and
the functions called for them (when called at all). It can debated which is
more useful, but the removal of the extra layer of potential errors wins.

Crucially though, we stop caring about "holes" in IOCTL assignment, which
makes it much easier for me to move pdump ioctls to their own range.

Signed-off-by: Luc Verhaegen <libv@codethink.co.uk>
Signed-off-by: Imre Deak <imre.deak@nokia.com>