sandbox: Rename sb_cmdline_option to sandbox_cmdline_option

The new name is longer but more clearly related to sandbox.

This is in a separate patch within the same series since some comments on the
SPI series rely on it.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Hung-ying Tyan <tyanh@chromium.org>
diff --git a/arch/sandbox/cpu/os.c b/arch/sandbox/cpu/os.c
index db66fd3..26f44cb 100644
--- a/arch/sandbox/cpu/os.c
+++ b/arch/sandbox/cpu/os.c
@@ -161,7 +161,7 @@
 
 int os_parse_args(struct sandbox_state *state, int argc, char *argv[])
 {
-	struct sb_cmdline_option **sb_opt = __u_boot_sandbox_option_start;
+	struct sandbox_cmdline_option **sb_opt = __u_boot_sandbox_option_start;
 	size_t num_options = __u_boot_sandbox_option_count();
 	size_t i;