IB/ipath: Misc changes to prepare for IB7220 introduction

The patch adds a number of minor changes to support newer HCAs:
 - New send buffer control bits
 - New error condition bits
 - Locking and initialization changes
 - More send buffers

Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>