Update the libgcc support for VxWorks AE/653

Update the libgcc support for VxWorks AE/653

2019-11-12  Olivier Hainque  <hainque@adacore.com>

	libgcc/

        * config/t-gthr-vxworksae: New file, add all the gthr-vxworks
        sources except the cxx0x support to LIB2ADDEH.  We don't support
        cxx0x on AE/653.
        * config/t-vxworksae: New file.

        * config.host: Handle *-*-vxworksae: Add the two aforementioned
	Makefile fragment files at their expected position in the tmake_file
	list, in accordance with what is done for other VxWorks variants.

From-SVN: r278250