Support exception handling on statically-linked binaries

Support exception handling on statically-linked binaries

The real-time dynamic linker handles exceptions on dynamically-linked
binaries through the dl_iterate_phdr function.  The RTLD isn't invoked
on statically-built executables so thrown exceptions weren't getting
handled.  There was a dummy dl_iterate_phdr function in libc with a
weak symbol that gets looked at when the rtld version isn't present.
This function was populated and gets called when the statically-linked
executable throws an exception.

It requires the GNU_EH_FRAME program header to be present.  The base
gcc 4.4 spec file was modified to emit this header for statically-built
binaries in addition to the dynamically lined ones.