drm: drop obsolete drm_core.h

The drm_core.h header contains a set of constants meant to be used
throughout DRM. However, as it turns out, they're each used just once and
don't bring any benefit. They're also grossly mis-named and lack
name-spacing. This patch inlines them, or moves them into drm_internal.h
as appropriate:

 - CORE_AUTHOR and CORE_DESC are inlined into corresponding MODULE_*()
   macros. It's just confusing having to follow 2 pointers when trying to
   find the definition of these fields. Grep'ping for MODULE_AUTHOR()
   should reveal the full information, if there's no strong reason not to.

 - CORE_NAME, CORE_DATE, CORE_MAJOR, CORE_MINOR, and CORE_PATCHLEVEL are
   inlined into the sysfs 'version' attribute. They're stripped
   everywhere else (which is just some printk() statements). CORE_NAME
   just doesn't make *any* sense, as we hard-code it in many places,
   anyway. The other constants are outdated and just serve
   binary-compatibility purposes. Hence, inline them in 'version' sysfs
   attribute (we might even try dropping it..).

 - DRM_IF_MAJOR and DRM_IF_MINOR are moved into drm_internal.h as they're
   only used by the global ioctl handlers. Furthermore, versioning
   interfaces breaks backports and as such is deprecated, anyway. We just
   keep them for historic reasons. I doubt anyone will ever modify them
   again.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20160901124837.680-6-dh.herrmann@gmail.com
diff --git a/drivers/gpu/drm/drm_sysfs.c b/drivers/gpu/drm/drm_sysfs.c
index 32dd821..9a37196 100644
--- a/drivers/gpu/drm/drm_sysfs.c
+++ b/drivers/gpu/drm/drm_sysfs.c
@@ -19,7 +19,6 @@
 #include <linux/export.h>
 
 #include <drm/drm_sysfs.h>
-#include <drm/drm_core.h>
 #include <drm/drmP.h>
 #include "drm_internal.h"
 
@@ -37,12 +36,7 @@
 	return kasprintf(GFP_KERNEL, "dri/%s", dev_name(dev));
 }
 
-static CLASS_ATTR_STRING(version, S_IRUGO,
-		CORE_NAME " "
-		__stringify(CORE_MAJOR) "."
-		__stringify(CORE_MINOR) "."
-		__stringify(CORE_PATCHLEVEL) " "
-		CORE_DATE);
+static CLASS_ATTR_STRING(version, S_IRUGO, "drm 1.1.0 20060810");
 
 /**
  * drm_sysfs_init - initialize sysfs helpers