apply suggestion from jocelyn fournier

in build.

	hyphen in it (like ds-cpl).

convert illegal chars in cpu flags to '_' for variable assignment

  Portable handling of "echo" without newline (bug#24605)
check-cpu:
  In developer script safe to use "printf", not "echo -n"

    
    - support additional platforms (OpenBSD, Darwin)
    - make use of /proc/cpuinfo CPU flag information
      (needed to distinguish EMT64 Xeons from normal ones)
    - chose the right CPU related options depending on 
      GCC version and target architecture
    - check if the chosen CPU type is actually supported
      by the GCC version , fallback to CPUs predecessor
      until test compile succeeds

   - Made a script that selects the best compiler optimizations for the current cpu.
   - Use the script from BUILD/SETUP.sh