Use shared globals to init __progname + environ

Initialize the __progname and environ global variables using
libc_shared_globals rather than KernelArgumentBlock.

Also: suppose the linker is invoked on an executable:

    linker prog [args...]

The first argument passed to main() and constructor functions is "prog"
rather than "linker". For consistency, this CL changes the BSD
__progname global from "linker" to "prog".

Bug: none
Test: bionic unit tests
Change-Id: I376d76953c9436706dbc53911ef6585c1acc1c31
diff --git a/libc/bionic/libc_init_dynamic.cpp b/libc/bionic/libc_init_dynamic.cpp
index 24f40ba..25d462f 100644
--- a/libc/bionic/libc_init_dynamic.cpp
+++ b/libc/bionic/libc_init_dynamic.cpp
@@ -85,7 +85,7 @@
 #endif
 
   __libc_init_globals(args);
-  __libc_init_common(args);
+  __libc_init_common();
 
   // Hooks for various libraries to let them know that we're starting up.
   __libc_globals.mutate(__libc_init_malloc);