drm/radeon/ni_dpm: Move 'ni_get_{pi, ps}()'s into shared header

Fixes the following W=1 kernel build warning(s):

 drivers/gpu/drm/radeon/ni_dpm.c:727:23: warning: no previous prototype for ‘ni_get_pi’ [-Wmissing-prototypes]
 727 | struct ni_power_info *ni_get_pi(struct radeon_device *rdev)
 | ^~~~~~~~~
 drivers/gpu/drm/radeon/ni_dpm.c:734:15: warning: no previous prototype for ‘ni_get_ps’ [-Wmissing-prototypes]
 734 | struct ni_ps *ni_get_ps(struct radeon_ps *rps)
 | ^~~~~~~~~

Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: amd-gfx@lists.freedesktop.org
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/radeon/ni_dpm.h

@@ -247,4 +247,7 @@ void ni_set_uvd_clock_after_set_eng_clock(struct radeon_device *rdev,
 
 bool ni_dpm_vblank_too_short(struct radeon_device *rdev);
 
+struct ni_power_info *ni_get_pi(struct radeon_device *rdev);
+struct ni_ps *ni_get_ps(struct radeon_ps *rps);
+
 #endif

drivers/gpu/drm/radeon/si_dpm.c

@@ -30,6 +30,7 @@
 #include "rv770.h"
 #include "radeon.h"
 #include "radeon_asic.h"
+#include "ni_dpm.h"
 #include "si_dpm.h"
 #include "sid.h"
 
@@ -1719,8 +1720,6 @@ static const struct si_powertune_data powertune_data_hainan =
 };
 
 struct evergreen_power_info *evergreen_get_pi(struct radeon_device *rdev);
-struct ni_power_info *ni_get_pi(struct radeon_device *rdev);
-struct ni_ps *ni_get_ps(struct radeon_ps *rps);
 
 extern int si_mc_load_microcode(struct radeon_device *rdev);
 extern void vce_v1_0_enable_mgcg(struct radeon_device *rdev, bool enable);