IO: add VR I/O Scheduler

file:0fec4b3fab511bc065261121f279e6f64038c35c -> file:ec3d9d292dfa788561c6c04e4ba239729f2d21ea
--- a/block/Makefile
+++ b/block/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_BLK_DEV_THROTTLING) += blk-
obj-$(CONFIG_IOSCHED_NOOP) += noop-iosched.o
obj-$(CONFIG_IOSCHED_DEADLINE) += deadline-iosched.o
obj-$(CONFIG_IOSCHED_CFQ) += cfq-iosched.o
+obj-$(CONFIG_IOSCHED_VR) += vr-iosched.o
obj-$(CONFIG_BLOCK_COMPAT) += compat_ioctl.o
obj-$(CONFIG_BLK_DEV_INTEGRITY) += blk-integrity.o