[Ada] Disable Support_Atomic_Primitives on x86_64 VxWorks

[Marc Poulhiès via Gcc-patches]

The current configuration of the x86-64 VxWorks runtimes does not support
atomic primitives. x86-64 VxWorks was missed from the previous patch.

Tested on x86_64-pc-linux-gnu, committed on trunk

gcc/ada/

        * libgnat/system-vxworks7-x86_64-kernel.ads: Set
        Support_Atomic_Primitives to false.
        * libgnat/system-vxworks7-x86_64-rtp-smp.ads: Ditto.
diff --git a/gcc/ada/libgnat/system-vxworks7-x86_64-kernel.ads b/gcc/ada/libgnat/system-vxworks7-x86_64-kernel.ads
--- a/gcc/ada/libgnat/system-vxworks7-x86_64-kernel.ads
+++ b/gcc/ada/libgnat/system-vxworks7-x86_64-kernel.ads
@@ -146,7 +146,7 @@ private
    Stack_Check_Probes        : constant Boolean := True;
    Stack_Check_Limits        : constant Boolean := False;
    Support_Aggregates        : constant Boolean := True;
-   Support_Atomic_Primitives : constant Boolean := True;
+   Support_Atomic_Primitives : constant Boolean := False;
    Support_Composite_Assign  : constant Boolean := True;
    Support_Composite_Compare : constant Boolean := True;
    Support_Long_Shifts       : constant Boolean := True;


diff --git a/gcc/ada/libgnat/system-vxworks7-x86_64-rtp-smp.ads b/gcc/ada/libgnat/system-vxworks7-x86_64-rtp-smp.ads
--- a/gcc/ada/libgnat/system-vxworks7-x86_64-rtp-smp.ads
+++ b/gcc/ada/libgnat/system-vxworks7-x86_64-rtp-smp.ads
@@ -149,7 +149,7 @@ private
    Stack_Check_Probes        : constant Boolean := True;
    Stack_Check_Limits        : constant Boolean := False;
    Support_Aggregates        : constant Boolean := True;
-   Support_Atomic_Primitives : constant Boolean := True;
+   Support_Atomic_Primitives : constant Boolean := False;
    Support_Composite_Assign  : constant Boolean := True;
    Support_Composite_Compare : constant Boolean := True;
    Support_Long_Shifts       : constant Boolean := True;