drm/amd/display: Add missing pipes registers for VGA enable/disable

Signed-off-by: Nevenko Stupar <Nevenko.Stupar@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dce/dce_hwseq.h

@@ -282,6 +282,8 @@ struct dce_hwseq_registers {
 	uint32_t D2VGA_CONTROL;
 	uint32_t D3VGA_CONTROL;
 	uint32_t D4VGA_CONTROL;
+	uint32_t D5VGA_CONTROL;
+	uint32_t D6VGA_CONTROL;
 	uint32_t VGA_TEST_CONTROL;
 	/* MMHUB registers. read only. temporary hack */
 	uint32_t VM_CONTEXT0_PAGE_TABLE_BASE_ADDR_HI32;