HPCC-9587 Ubuntu 12.04 32bit eclcc cores on constant folding

Seems like we can end up with additional instructions between
the two asm sections that rely on the value of esp having been
already restored.

Signed-off-by: Richard Chapman <rchapman@hpccsystems.com>
Merge pull request #4581 from richardkchapman/32-bit-fold-core

HPCC-9587 Ubuntu 12.04 32bit eclcc cores on constant folding

Reviewed-by: Gavin Halliday <ghalliday@hpccsystems.com>