drm/amdgpu: Fix fall-through warnings for Clang

In preparation to enable -Wimplicit-fallthrough for Clang, fix multiple
warnings by explicitly adding multiple break statements instead of just
letting the code fall through to the next case.

Link: https://github.com/KSPP/linux/issues/115
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/gfx_v10_0.c

@@ -8661,6 +8661,7 @@ static int gfx_v10_0_set_priv_inst_fault_state(struct amdgpu_device *adev,
 		WREG32_FIELD15(GC, 0, CP_INT_CNTL_RING0,
 			       PRIV_INSTR_INT_ENABLE,
 			       state == AMDGPU_IRQ_STATE_ENABLE ? 1 : 0);
+		break;
 	default:
 		break;
 	}

drivers/gpu/drm/amd/amdgpu/gfx_v9_0.c

@@ -5687,6 +5687,7 @@ static int gfx_v9_0_set_priv_inst_fault_state(struct amdgpu_device *adev,
 		WREG32_FIELD15(GC, 0, CP_INT_CNTL_RING0,
 			       PRIV_INSTR_INT_ENABLE,
 			       state == AMDGPU_IRQ_STATE_ENABLE ? 1 : 0);
+		break;
 	default:
 		break;
 	}

drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c

@@ -502,6 +502,7 @@ static int gmc_v9_0_vm_fault_interrupt_state(struct amdgpu_device *adev,
 				WREG32(reg, tmp);
 			}
 		}
+		break;
 	default:
 		break;
 	}

drivers/gpu/drm/amd/amdgpu/vi.c

@@ -1645,6 +1645,7 @@ static int vi_common_set_clockgating_state(void *handle,
 	case CHIP_POLARIS12:
 	case CHIP_VEGAM:
 		vi_common_set_clockgating_state_by_smu(adev, state);
+		break;
 	default:
 		break;
 	}