Change the interfaces for backend methods that create statements to
always pass in the enclosing Bfunction for the statement. Having the
function available simplifies things if a temporary variable has to be
created during the construction of a statement.
This also includes a change to the Mark_lvalue_varexprs helper
class to handle indirections on the left hand side of assignments
(e.g. "*x.y = ...").
Reviewed-on: https://go-review.googlesource.com/34471
* go-gcc.cc (Gcc_backend::expression_statement): Add Bfunction*
parameter.
(Gcc_backend::init_statement): Likewise.
(Gcc_backend::assignment_statement): Likewise.
(Gcc_backend::if_statement): Likewise.
From-SVN: r243766
