* lang.opt: Add -fgo-pkgpath.
* go-lang.c (go_pkgpath): New static variable.
(go_prefix): New static variable.
(go_langhook_init): Pass go_pkgpath and go_prefix to
go_create_gogo.
(go_langhook_handle_option): Handle -fgo-pkgpath. Change
-fgo-prefix handling to just set go_prefix.
* go-c.h (go_set_prefix): Don't declare.
(go_create_gogo): Add pkgpath and prefix to declaration.
* go-gcc.cc (Gcc_backend::global_variable): Change unique_prefix
to pkgpath. Don't include the package name in the asm name.
* gccgo.texi (Invoking gccgo): Document -fgo-pkgpath. Update the
docs for -fgo-prefix.
From-SVN: r187356
