re PR go/61880 (Linking with external functions in C does not work in GO when using...

re PR go/61880 (Linking with external functions in C does not work in GO when using gccgo, while it works in gc)

	PR go/61880
compiler: symbol names should have '.' replaced with '_'

Package and symbol names issued by the cgo tool and compiler
should be the same for the object files to link.

A minimal change to fix only:
   https://code.google.com/p/gofrontend/issues/detail?id=36
and
   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61880

From-SVN: r215810