drm/amd/display: Add DCN3.1 blocks to the DC Makefile

Preparation for compiling DCN3.1 support.
Acked-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/Makefile

@@ -34,6 +34,9 @@ DC_LIBS += dcn30
 DC_LIBS += dcn301
 DC_LIBS += dcn302
 DC_LIBS += dcn303
+ifdef CONFIG_DRM_AMD_DC_DCN3_1
+DC_LIBS += dcn31
+endif
 endif
 
 DC_LIBS += dce120

drivers/gpu/drm/amd/display/dc/dcn31/Makefile

+#
+# (c) Copyright 2020 Advanced Micro Devices, Inc. All the rights reserved
+#
+#  All rights reserved.  This notice is intended as a precaution against
+#  inadvertent publication and does not imply publication or any waiver
+#  of confidentiality.  The year included in the foregoing notice is the
+#  year of creation of the work.
+#
+#  Authors: AMD
+#
+# Makefile for dcn31.
+
+DCN31 = dcn31_resource.o dcn31_hubbub.o dcn31_hwseq.o dcn31_init.o dcn31_hubp.o \
+	dcn31_dccg.o dcn31_optc.o dcn31_dio_link_encoder.o dcn31_panel_cntl.o
+
+CFLAGS_$(AMDDALPATH)/dc/dcn31/dcn31_resource.o := -mhard-float -msse
+
+ifdef CONFIG_CC_IS_GCC
+ifeq ($(call cc-ifversion, -lt, 0701, y), y)
+IS_OLD_GCC = 1
+endif
+endif
+
+ifdef IS_OLD_GCC
+# Stack alignment mismatch, proceed with caution.
+# GCC < 7.1 cannot compile code using `double` and -mpreferred-stack-boundary=3
+# (8B stack alignment).
+CFLAGS_$(AMDDALPATH)/dc/dcn31/dcn31_resource.o += -mpreferred-stack-boundary=4
+else
+CFLAGS_$(AMDDALPATH)/dc/dcn31/dcn31_resource.o += -msse2
+endif
+
+AMD_DAL_DCN31 = $(addprefix $(AMDDALPATH)/dc/dcn31/,$(DCN31))
+
+AMD_DISPLAY_FILES += $(AMD_DAL_DCN31)