doc: add abbreviation in docs

add abbrevitations in conf.py

Signed-off-by: Wayne Ren <wei.ren@synopsys.com>

Author: Wayne Ren

doc/documents/conf.py

@@ -185,4 +185,10 @@
 
 rst_epilog =  u"""
 .. |arc| replace:: DesignWare® ARC® processors
+.. |embarc| replace:: embARC OSP
+.. |iotdk| replace:: IoT Development Kit
+.. |hsdk| replace:: HS Development Kit
+.. |emsk| replace:: EM Starter Kit
+.. |mwdt| replace:: MetaWare Development Toolkit
+.. |arcgnu| replace:: GNU Toolchain for ARC Processors
 """