radeonsi: move r600_viewport.c to si_viewport.c

This is purely a file-move + #include fixup + build system changes.
Other cleanups will follow in subsequent commits.

Reviewed-by: Marek Olšák <marek.olsak@amd.com>

src/gallium/drivers/radeon/Makefile.sources

@@ -11,7 +11,6 @@ C_SOURCES := \
 	r600_streamout.c \
 	r600_test_dma.c \
 	r600_texture.c \
-	r600_viewport.c \
 	radeon_uvd.c \
 	radeon_uvd.h \
 	radeon_vcn_dec.c \

src/gallium/drivers/radeonsi/Makefile.sources

@@ -30,5 +30,6 @@ C_SOURCES := \
 	si_state_binning.c \
 	si_state_draw.c \
 	si_state_shaders.c \
+	si_state_viewport.c \
 	si_state.h \
 	si_uvd.c

src/gallium/drivers/radeonsi/si_state_viewport.c

@@ -21,7 +21,7 @@
  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 
-#include "r600_cs.h"
+#include "radeon/r600_cs.h"
 #include "util/u_viewport.h"
 #include "tgsi/tgsi_scan.h"