Patch against 7.2.1 sources. Uses Solaris Intimate Shared Memory

for Solaris on SPARC.  Scott Brunza (sbrunza@sonalysts.com) gets
credit for identifying the issue, making the change, and doing
the regression tests.

Earlier testing on 7.2rc2 and 7.2 showed performance gains of
1% to 10% on pgbench, osdb-pg, and some locally developed apps.

Solaris Intimate Shared Memory is described in "SOLARIS INTERNALS
Core Kernel Components" by Jim Mauro and Richard McDougall,
Copyright 2001 Sun Microsystem, Inc.  ISBN 0-13-022496-0

P.J. "Josh" Rovero