remote-sim.c: Fix arg variables conflicts

remote-sim.c: Fix arg variables conflicts

The recent change introducing gdb_argv introduced some build failures in
remote-sim.c.

  /home/emaisin/src/binutils-gdb/gdb/remote-sim.c: In function 'void gdbsim_load(target_ops*, const char*, int)':
  /home/emaisin/src/binutils-gdb/gdb/remote-sim.c:573:22: error: conflicting declaration 'gdb_argv argv'
     gdb_argv argv (args);
                        ^
  /home/emaisin/src/binutils-gdb/gdb/remote-sim.c:565:10: note: previous declaration as 'char** argv'
     char **argv;
            ^~~~
  /home/emaisin/src/binutils-gdb/gdb/remote-sim.c: In function 'void gdbsim_open(const char*, int)':
  /home/emaisin/src/binutils-gdb/gdb/remote-sim.c:730:25: error: declaration of 'gdb_argv args' shadows a parameter
     gdb_argv args (arg_buf);

In gdbsim_load, the new gdb_argv object conflicts with old char **argv
variable.  I think the old variable should be removed.

In gdbsim_open, the new gdb_argv object conflicts with the args
parameter.  This patch renames it to argv.

Built-tested for a mips host.

gdb/ChangeLog:

	* remote-sim.c (gdbsim_load): Remove char **argv local variable.
	(gdbsim_open): Rename gdb_argv args object to argv.