Removed EXPERIMENTAL_KPROBE_SDT support.

Removed EXPERIMENTAL_KPROBE_SDT support.

* tapsets.cxx (dwarf_derived_probe_group): Removed 'has_semaphores' member
  variable.
  (dwarf_derived_probe_group::enroll): Throw an error if we have a
  semaphore.
  (dwarf_derived_probe_group::emit_module_decls): No longer emit semaphore
  support in struct stap_dwarf_probe or include kprobes-common.c.
  (dwarf_derived_probe_group::emit_module_init): No longer initialize
  semaphore info in struct stap_dwarf_probe.
  (dwarf_derived_probe_group::emit_module_exit): No longer decrement
  semaphores on module exit.
  (sdt_query::have_kprobe): Remove kprobe2_type support.
  (sdt_query::handle_probe_entry): Ditto.
  (sdt_query::iterate_over_probe_entries): Ditto.
  (sdt_query::convert_location): Ditto.
* sdt_types.h: Remove KPROBE2_TYPE define and kprobe2_type enum value.
* runtime/kprobes-common.c: Deleted.
* runtime/kprobes-common.h: Removed deleted function declarations.
* scripts/probe_perf/bench.sh: Remove EXPERIMENTAL_KPROBE_SDT test.
* testsuite/sys/sdt.h: Removed EXPERIMENTAL_KPROBE_SDT support.
* testsuite/systemtap.base/sdt.exp: Ditto.
* testsuite/systemtap.base/sdt_misc.exp: Ditto.