Add -lssp_nonshared to GCC's LIB_SPEC unconditionally

[b. f.]

On Tue Aug 3 15:22:00 UTC 2010, Jeremie Le Hen wrote:
...
>I therefore propose the following change to always link in
>libssp_nonshared.a.  I think this change is harmless when the symbol is
>not needed in one of the objects linked together since the linker won't
>pull in the library member "ssp-local.o" in the target object.

Will this do the right thing when the base system is built
WITHOUT_SSP? How about the case of
WITHOUT_DYNAMICROOT/NOSHARED/NO_SHARED=yes, with and without this
change?  Are changes to the specs of the lang/gcc* ports needed? What
about clang?

b.