Add crt0.S and linker scripts for EMSK into toolchain

Wiki refers to my personal Gist to download those, which is not cool. So
I'm adding those files into repository like has already been done with
Opella-XD files. Those files are updated to EMSK v2.0 and developed by
Claudiu.

Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>