MAINTAINERS: Fix Hyperv vIOMMU driver file name

The Hyperv vIOMMU file name should be "hyperv-iommu.c" rather
than "hyperv_iommu.c". This patch is to fix it.
Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

MAINTAINERS

@@ -7454,7 +7454,7 @@ F:	drivers/net/hyperv/
 F:	drivers/scsi/storvsc_drv.c
 F:	drivers/uio/uio_hv_generic.c
 F:	drivers/video/fbdev/hyperv_fb.c
-F:	drivers/iommu/hyperv_iommu.c
+F:	drivers/iommu/hyperv-iommu.c
 F:	net/vmw_vsock/hyperv_transport.c
 F:	include/clocksource/hyperv_timer.h
 F:	include/linux/hyperv.h