[testsuite patch] add __ARM_ARCH check for arm_v8_neon_ok

[Janis Johnson]

The check for effective target arm_v8_neon_ok passes even if __ARM_ARCH
is not 8 or greater, but then some tests fail because intrinsic functions
used in the test have not been declared.  This patch requires that
__ARM_ARCH be 8 or greater.  Tested for arm-none-linux-gnu for mainline
and 4.9 with a variety of multilib flags.

OK for mainline and the 4.9 branch?

Janis

2014-08-11  Janis Johnson  <jani...@codesourcery.com>

        * lib/target/supports.exp
        (check_effective_target_arm_v8_neon_ok_nocache): Check for armv8
        or later.

Index: gcc/testsuite/lib/target-supports.exp
===================================================================
--- gcc/testsuite/lib/target-supports.exp       (revision 213831)
+++ gcc/testsuite/lib/target-supports.exp       (working copy)
@@ -2578,6 +2578,9 @@
     if { [check_effective_target_arm32] } {
        foreach flags {"" "-mfloat-abi=softfp" "-mfpu=neon-fp-armv8" 
"-mfpu=neon-fp-armv8 -mfloat-abi=softfp"} {
            if { [check_no_compiler_messages_nocache arm_v8_neon_ok object {
+               #if __ARM_ARCH < 8
+               #error not armv8 or later
+               #endif
                #include "arm_neon.h"
                void
                foo ()