drm/amd/display: Pack DMCU iRAM alignment

[Why]
When the DMCU's iRAM definition was moved to the newly created
power_helpers, a #pragma pack was lost, causing the iRAM to be misaligned

[How]
Restore the #pragma pack

Signed-off-by: Josip Pavic <Josip.Pavic@amd.com>
Reviewed-by: Anthony Koo <Anthony.Koo@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/amd/display/modules/power/power_helpers.c b/drivers/gpu/drm/amd/display/modules/power/power_helpers.c
index 00f63b7..c11a443 100644
--- a/drivers/gpu/drm/amd/display/modules/power/power_helpers.c
+++ b/drivers/gpu/drm/amd/display/modules/power/power_helpers.c
@@ -57,6 +57,7 @@
 #define NUM_POWER_FN_SEGS 8
 #define NUM_BL_CURVE_SEGS 16
 
+#pragma pack(push, 1)
 /* NOTE: iRAM is 256B in size */
 struct iram_table_v_2 {
 	/* flags                      */
@@ -100,6 +101,7 @@
 	uint8_t dummy8;							/* 0xfe       */
 	uint8_t dummy9;							/* 0xff       */
 };
+#pragma pack(pop)
 
 static uint16_t backlight_8_to_16(unsigned int backlight_8bit)
 {