drm/amdgpu: fix memory leak in CGS (FW info)

Previously requested FW pointer should not be
overwritten on a subsequent call.
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NMykola Lysenko <Mykola.Lysenko@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

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

@@ -735,6 +735,7 @@ static int amdgpu_cgs_get_firmware_info(struct cgs_device *cgs_device,
 		const uint8_t *src;
 		const struct smc_firmware_header_v1_0 *hdr;
 
+		if (!adev->pm.fw) {
 			switch (adev->asic_type) {
 			case CHIP_TONGA:
 				strcpy(fw_name, "amdgpu/tonga_smc.bin");
@@ -772,6 +773,7 @@ static int amdgpu_cgs_get_firmware_info(struct cgs_device *cgs_device,
 				adev->pm.fw = NULL;
 				return err;
 			}
+		}
 
 		hdr = (const struct smc_firmware_header_v1_0 *)	adev->pm.fw->data;
 		adev->pm.fw_version = le32_to_cpu(hdr->header.ucode_version);