Fix gcc-4.5 HEAD warnings for enum ada_operator.
* Makefile.in (HFILES_NO_SRCDIR): Add ada-operator.inc.
* ada-lang.h (enum ada_operator): Move it to ...
* ada-operator.inc: ... a new file.
* expression.h (enum exp_opcode): Include ada-operator.inc.
New element OP_UNUSED_LAST. Update comment for OP_EXTENDED0.
gdb/
Fix gcc-4.5 HEAD warnings for GDB_FORM_cached_string.
* dwarf2read.c (GDB_FORM_cached_string)
(dwarf_form_name <GDB_FORM_cached_string>): Remove.
(struct attribute <dwarf_form>): Reduce the bit width.
(struct attribute <string_is_canonical>, DW_STRING_IS_CANONICAL): New.
(read_attribute_value <DW_FORM_string>)
(read_attribute_value <DW_FORM_strp>): Initialize
DW_STRING_IS_CANONICAL.
(dwarf2_name, dump_die_shallow <DW_FORM_string>)
(dump_die_shallow <DW_FORM_strp>): Update the code using former
GDB_FORM_cached_string.
