target/hexagon: idef-parser fix leak of init_list

target/hexagon: idef-parser fix leak of init_list

gen_inst_init_args() is called for instructions using a predicate as an
rvalue. Upon first call, the list of arguments which might need
initialization init_list is freed to indicate that they have been
processed. For instructions without an rvalue predicate,
gen_inst_init_args() isn't called and init_list will never be freed.

Free init_list from free_instruction() if it hasn't already been freed.
A comment in free_instruction is also updated.

Signed-off-by: Anton Johansson <anjo@rev.ng>
Reviewed-by: Taylor Simpson <ltaylorsimpson@gmail.com>
Reviewed-by: Brian Cain <bcain@quicinc.com>
Message-Id: <20240523125901.27797-4-anjo@rev.ng>
Signed-off-by: Brian Cain <bcain@quicinc.com>