package/intel-mediadriver: fix option

Replace INSTALL_DRIVERS_SYSCONF by INSTALL_DRIVER_SYSCONF which is the
correct name since version 18.2.0 and
https://github.com/intel/media-driver/commit/81796c8a9e44b878e26064c898e0f4730e8220cf

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

package/intel-mediadriver/intel-mediadriver.mk

@@ -22,7 +22,7 @@ INTEL_MEDIADRIVER_DEPENDENCIES = \
 INTEL_MEDIADRIVER_SUPPORTS_IN_SOURCE_BUILD = NO
 
 INTEL_MEDIADRIVER_CONF_OPTS = \
-	-DINSTALL_DRIVERS_SYSCONF=OFF \
+	-DINSTALL_DRIVER_SYSCONF=OFF \
 	-DMEDIA_RUN_TEST_SUITE=OFF
 
 $(eval $(cmake-package))