The -march=armv5 and armv5e options have been deprecated in GCC 7 [1].
This patch removes support for them.
It's mostly mechanical stuff. The functionality that was previously
gated on arm_arch5 is now gated on arm_arch5t and the functionality
that was gated on arm_arch5e is now gated on arm_arch5te.

A path in TARGET_OS_CPP_BUILTINS for VxWorks is now unreachable and
therefore is deleted.

References to armv5 and armv5e are deleted/updated throughout the
source tree and testsuite.

Bootstrapped and tested on arm-none-linux-gnueabihf.
Also built a cc1 for arm-wrs-vxworks as a sanity check.

        * config/arm/arm-cpus.in (armv5, armv5e): Delete features.
        (armv5t, armv5te): New features.
        (ARMv5, ARMv5e): Delete fgroups.
        (ARMv5t, ARMv5te): Adjust for above changes.
        (ARMv6m): Likewise.
        (armv5, armv5e): Delete arches.
        * config/arm/arm.md (*call_reg_armv5): Use arm_arch5t instead of
        arm_arch5.
        (*call_reg_arm): Likewise.
        (*call_value_reg_armv5): Likewise.
        (*call_value_reg_arm): Likewise.
        (*call_symbol): Likewise.
        (*call_value_symbol): Likewise.
        (*sibcall_insn): Likewise.
        (*sibcall_value_insn): Likewise.
        (clzsi2): Likewise.
        (prefetch): Likewise.
        (define_split and define_peephole2 dependent on arm_arch5):
        Likewise.
        * config/arm/arm.h (TARGET_LDRD): Use arm_arch5te instead of
        arm_arch5e.
        (TARGET_ARM_QBIT): Likewise.
        (TARGET_DSP_MULTIPLY): Likewise.
        (enum base_architecture): Delete BASE_ARCH_5, BASE_ARCH_5E.
        (arm_arch5, arm_arch5e): Delete.
        (arm_arch5t, arm_arch5te): Declare.
        * config/arm/arm.c (arm_arch5, arm_arch5e): Delete.
        (arm_arch5t): Declare.
        (arm_option_reconfigure_globals): Update for the above.
        (arm_options_perform_arch_sanity_checks): Update comment, replace
        use of arm_arch5 with arm_arch5t.
        (use_return_insn): Likewise.
        (arm_emit_call_insn): Likewise.
        (output_return_instruction): Likewise.
        (arm_final_prescan_insn): Likewise.
        (arm_coproc_builtin_available): Likewise.
        * config/arm/arm-c.c (arm_cpu_builtins): Replace arm_arch5 and
        arm_arch5e with arm_arch5t and arm_arch5te.
        * config/arm/arm-protos.h (arm_arch5, arm_arch5e): Delete.
        (arm_arch5t, arm_arch5te): Declare.
        * config/arm/arm-tables.opt: Regenerate.
        * config/arm/t-arm-elf: Remove references to armv5, armv5e.
        * config/arm/t-multilib: Likewise.
        * config/arm/thumb1.md (*call_reg_thumb1_v5): Check arm_arch5t
        instead of arm_arch5.
        (*call_reg_thumb1): Likewise.
        (*call_value_reg_thumb1_v5): Likewise.
        (*call_value_reg_thumb1): Likewise.
        * config/arm/vxworks.h (TARGET_OS_CPP_BUILTINS): Remove now
        unreachable path.
        * doc/invoke.texi (ARM Options): Remove references to armv5, armv5e.

        * gcc.target/arm/pr40887.c: Update comment.
        * lib/target-supports.exp: Don't generate effective target checks
        and related helpers for armv5.  Update comment.
        * gcc.target/arm/armv5_thumb_isa.c: Delete.
        * gcc.target/arm/di-longlong64-sync-withhelpers.c: Update effective
        target check and options.

        * config/arm/libunwind.S: Update comment relating to armv5.

From-SVN: r260362