nvidia340: add patch to add DRIVER_LEGACY to nv-drm.c (#5575)

The nvidia340 legacy driver fails to load on the 4.9 kernel.
This commit adds a patch written by ejmarkow, taken from
https://devtalk.nvidia.com/default/topic/982052/linux/latest-nvidia-driver-340-101-builds-compiles-properly-but-fails-to-load-has-errors-with-linux-kernel-4-9-resolved-with-patch-/
that adds DRIVER_LEGACY to the driver features in nv-drm.c.

srcpkgs/nvidia340/files/patch_nv1.diff

@@ -0,0 +1,14 @@
+--- kernel/nv-drm.c	2016-12-15 12:41:26.000000000 +0100
++++ kernel/nv-drm.c	2016-12-15 12:58:48.000000000 +0100
+@@ -115,7 +115,11 @@
+ };
+ 
+ static struct drm_driver nv_drm_driver = {
++#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 9, 0)
++    .driver_features = DRIVER_GEM | DRIVER_PRIME | DRIVER_LEGACY,
++#else
+     .driver_features = DRIVER_GEM | DRIVER_PRIME,
++#endif
+     .load = nv_drm_load,
+     .unload = nv_drm_unload,
+     .fops = &nv_drm_fops,

srcpkgs/nvidia340/template

@@ -4,7 +4,7 @@ _desc="NVIDIA drivers (GeForce 8, 9, 9M, 100, 100M, 200, 300 series)"
 
 pkgname=nvidia340
 version=340.101
-revision=1
+revision=2
 maintainer="Juan RP <xtraeme@voidlinux.eu>"
 license="Proprietary NVIDIA license"
 homepage="http://www.nvidia.com"
@@ -37,9 +37,12 @@ do_extract() {
 	./${_pkg}.run --extract-only
 	rm -f ${_pkg}.run
 }
+
 do_configure() {
 	cd ${_pkg}
+	patch -p0 < ${FILESDIR}/patch_nv1.diff
 }
+
 do_install() {
 	cd ${_pkg}