drm/nouveau/secboot: Make acr_r352_ls_gpccs_func static

Fix sparse warning:

drivers/gpu/drm/nouveau/nvkm/subdev/secboot/acr_r352.c:1092:1:
 warning: symbol 'acr_r352_ls_gpccs_func' was not declared. Should it be static?
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nvkm/subdev/secboot/acr_r352.c

@@ -1088,7 +1088,7 @@ acr_r352_ls_gpccs_func_0 = {
 	.lhdr_flags = LSF_FLAG_FORCE_PRIV_LOAD,
 };
 
-const struct acr_r352_ls_func
+static const struct acr_r352_ls_func
 acr_r352_ls_gpccs_func = {
 	.load = acr_ls_ucode_load_gpccs,
 	.version_max = 0,