main: Added entry point for glCreateTransformFeedbacks

v2: Review from Laura Ekstrand
- generate the name of the gl method once
- shorten some lines to stay in the 78 chars limit

v3: Review from Fredrik Höglund <fredrik@kde.org>
- rename gl_mthd_name to func
- set EverBound in _mesa_create_transform_feedbacks in the dsa case

v4:
- rename _mesa_create_transform_feedbacks to create_transform_feedbacks and
  make it static

Reviewed-by: Laura Ekstrand <laura@jlekstrand.net>
Signed-off-by: Martin Peres <martin.peres@linux.intel.com>

src/mapi/glapi/gen/ARB_direct_state_access.xml

@@ -7,6 +7,13 @@
    <enum name="QUERY_TARGET"    value="0x82EA"/>
    <enum name="TEXTURE_BINDING" value="0x82EB"/>
 
+   <!-- Transform Feedback object functions -->
+
+  <function name="CreateTransformFeedbacks" offset="assign">
+      <param name="n" type="GLsizei" />
+      <param name="ids" type="GLuint *" />
+   </function>
+
    <!-- Buffer object functions -->
 
    <function name="CreateBuffers" offset="assign">