package/nvidia-driver: define IGNORE_CC_MISMATCH

Leverage IGNORE_CC_MISMATCH for kernel module builds to avoid an issue
where NVIDIA's `cc_version_check` in kernel/conftest.sh may fail due
to matching on the pkgversion substring of the GCC version string in
the kernel's include/generated/compile.h.

Signed-off-by: Vincent Fazio <vfazio@xes-inc.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
(cherry picked from commit 30a79ffdb0d1197fb4304c46ec60f71040d68eb8)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/nvidia-driver/nvidia-driver.mk

@@ -137,6 +137,7 @@ endif
 # because they don't recognise the usual variables set by the kernel
 # build system. We also need to tell them what modules to build.
 NVIDIA_DRIVER_MODULE_MAKE_OPTS = \
+	IGNORE_CC_MISMATCH=1 \
 	NV_KERNEL_SOURCES="$(LINUX_DIR)" \
 	NV_KERNEL_OUTPUT="$(LINUX_DIR)" \
 	NV_KERNEL_MODULES="$(NVIDIA_DRIVER_MODULES)"