hdf5_ep

[svn-r16789] Bug Fix (Bug 1398):
For gcc v4.3 and v4.4, with production mode,
if -O3 is used, H5Tinit.c would fail to compile. Actually bad H5Tinit.c is
produced.

If -O (same as -O1) is used, H5Tinit.c compiled okay but test/dt_arith
would fail with:
Testing hard normalized long double -> signed char conversions        time: comm
and terminated abnormally

When -O0 (no optimizatio) is used, H5Tinit.c compilete okay and all tests
passed.

Solution:
Changed the config/gnu-flags to use -O0 for gcc v4.3 and 4.4 for production
flags  for now so that build and tests would work. Still need to investigate
if the error is due to Gcc optimization bug or our code errors.

Tested:
In liberty with gcc43 and gcc44. Also, tested in jam and smirom with
older versions of gcc.
There are no gcc 43 or 44 compilers installed in other THG machines that
I know.