drm/amdgpu/vcn: Modify mismatched function name

No functional modification involved.

drivers/gpu/drm/amd/amdgpu/vcn_v4_0_3.c:374: warning: expecting prototype for vcn_v4_0_mc_resume_dpg_mode(). Prototype was for vcn_v4_0_3_mc_resume_dpg_mode() instead.
drivers/gpu/drm/amd/amdgpu/vcn_v4_0_3.c:631: warning: expecting prototype for vcn_v4_0_enable_clock_gating(). Prototype was for vcn_v4_0_3_enable_clock_gating() instead.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Link: https://bugzilla.openanolis.cn/show_bug.cgi?id=5284


Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>