Simplify and improve the performance of the sqlite3VdbeMemGrow() routine.
In the OP_MakeRecord opcode, factor out affinity changes into separate loop,
for a slight performance advantage.
Avoid unnecessary calls to sqlite3VdbeSerialType() from within
sqlite3VdbeSerialPut().
Do not run the tool/vdbe-compress.tcl script that generates the
vdbeExecUnion object that reduces the size of the sqlite3VdbeExec()
stack frame unless the SQLITE_SMALL_STACK compile-time option is
specified as on of the OPTS in the makefile.  The vdbeExecUnion object
gets in the way of C-compiler optimizer and results in slightly slower code.
Fix harmless compiler warning.