glx: don't expose systemTimeExtension for DRI2/DRI3/DRISW

Used/applicable to only dri1 drivers.

Signed-off-by: Emil Velikov <emil.l.velikov@gmail.com>
diff --git a/src/glx/dri2_glx.c b/src/glx/dri2_glx.c
index d6eb281..5b93f2f 100644
--- a/src/glx/dri2_glx.c
+++ b/src/glx/dri2_glx.c
@@ -1393,8 +1393,6 @@
    else
       pdp->loader_extensions[i++] = &dri2LoaderExtension.base;
    
-   pdp->loader_extensions[i++] = &systemTimeExtension.base;
-
    pdp->loader_extensions[i++] = &dri2UseInvalidate.base;
 
    pdp->loader_extensions[i++] = NULL;
diff --git a/src/glx/dri3_glx.c b/src/glx/dri3_glx.c
index 42a94f9..9c15395 100644
--- a/src/glx/dri3_glx.c
+++ b/src/glx/dri3_glx.c
@@ -511,7 +511,6 @@
 
 static const __DRIextension *loader_extensions[] = {
    &imageLoaderExtension.base,
-   &systemTimeExtension.base,
    &dri3UseInvalidate.base,
    NULL
 };
diff --git a/src/glx/drisw_glx.c b/src/glx/drisw_glx.c
index 241ac7f..110b7f8 100644
--- a/src/glx/drisw_glx.c
+++ b/src/glx/drisw_glx.c
@@ -219,7 +219,6 @@
 };
 
 static const __DRIextension *loader_extensions[] = {
-   &systemTimeExtension.base,
    &swrastLoaderExtension.base,
    NULL
 };