* arm.cc (Target_arm::do_define_standard_symbols): New method.
(Target_arm::do_finalize_sections): Remove code which defines
__exidx_start and __exidx_end. Make symbol table parameter
anonymous as it is not used.
* gold.cc (queue_middle_tasks): Call target hook to define any
target-specific symbols.
* target.h (Target::define_standard_symbols): New method.
(Target::do_define_standard_symbols): Same.
* testsuite/Makefile.am (arm_exidx_test): Dump relocations also.
* testsuite/Makefile.in: Regenerate.
* testsuite/arm_exidx.s: Generate data relocations for __exidx_start
and __exidx_end.
* testsuite/arm_exidx_test.sh: Check that no unused dynamic
relocations are generated for __exidx_start and __exidx_end.
* arm.cc (Arm_output_section::Arm_output_section): Set SHF_LINK_ORDER
flag of a SHT_ARM_EXIDX section.
* testsuite/Makefile.am (arm_exidx_test): New test rules.
* testsuite/Makefile.in: Regenerate.
* testsuite/arm_exidx_test.s: New file.
* testsuite/arm_exidx_test.sh: Same.
