libgomp: Update to version 4.3.5.
This is a partial revert of r282115, to bring the fromal upstream
libgomp from GCC 4.3.5 Release under LGPLv2.1+.
This is only brought to ease the ongoing development of the CPU
affinity support.
This shall not be MFC'd.
This is not likely to make it into a release and is basically disabled
but should still be useful for testing.
Obtained from: GCC pre-4.3 (rev. 123494, 125542; LGPLv2.1+)
