drm/radeon: add W|RREG32_IDX for MM_INDEX|DATA based mmio accesss

Just refactoring to make the next patche simpler. Now all indirect register
access in the new modesetting driver should go through the r100_mm_(w|r)reg
fucntions.

RADEON_READ_MM from the old driver seems to be totally unused, so just kill
it.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/radeon/r100.c b/drivers/gpu/drm/radeon/r100.c
index 376884f..ae4c857 100644
--- a/drivers/gpu/drm/radeon/r100.c
+++ b/drivers/gpu/drm/radeon/r100.c
@@ -4135,9 +4135,10 @@
 	return 0;
 }
 
-uint32_t r100_mm_rreg(struct radeon_device *rdev, uint32_t reg)
+uint32_t r100_mm_rreg(struct radeon_device *rdev, uint32_t reg,
+		      bool always_indirect)
 {
-	if (reg < rdev->rmmio_size)
+	if (reg < rdev->rmmio_size && !always_indirect)
 		return readl(((void __iomem *)rdev->rmmio) + reg);
 	else {
 		writel(reg, ((void __iomem *)rdev->rmmio) + RADEON_MM_INDEX);
@@ -4145,9 +4146,10 @@
 	}
 }
 
-void r100_mm_wreg(struct radeon_device *rdev, uint32_t reg, uint32_t v)
+void r100_mm_wreg(struct radeon_device *rdev, uint32_t reg, uint32_t v,
+		  bool always_indirect)
 {
-	if (reg < rdev->rmmio_size)
+	if (reg < rdev->rmmio_size && !always_indirect)
 		writel(v, ((void __iomem *)rdev->rmmio) + reg);
 	else {
 		writel(reg, ((void __iomem *)rdev->rmmio) + RADEON_MM_INDEX);