radv: program a default point size.

Along the lines of what
3b804819 anv: Default PointSize to 1.0 if not written by the shader
does for anv, program a default point size in the hw of 1.0.

This preempt fixes a bunch of geom shader tests.

Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Cc: "17.0" <mesa-stable@lists.freedesktop.org>
Signed-off-by: Dave Airlie <airlied@redhat.com>
(cherry picked from commit 2ab2be092d15ddb449b4a215609705bae68089a0)
diff --git a/src/amd/vulkan/radv_cmd_buffer.c b/src/amd/vulkan/radv_cmd_buffer.c
index c6f238b..c62d275 100644
--- a/src/amd/vulkan/radv_cmd_buffer.c
+++ b/src/amd/vulkan/radv_cmd_buffer.c
@@ -438,7 +438,8 @@
 			       raster->spi_interp_control);
 
 	radeon_set_context_reg_seq(cmd_buffer->cs, R_028A00_PA_SU_POINT_SIZE, 2);
-	radeon_emit(cmd_buffer->cs, 0);
+	unsigned tmp = (unsigned)(1.0 * 8.0);
+	radeon_emit(cmd_buffer->cs, S_028A00_HEIGHT(tmp) | S_028A00_WIDTH(tmp));
 	radeon_emit(cmd_buffer->cs, S_028A04_MIN_SIZE(radv_pack_float_12p4(0)) |
 		    S_028A04_MAX_SIZE(radv_pack_float_12p4(8192/2))); /* R_028A04_PA_SU_POINT_MINMAX */