Correct SPL use of CMD_SHA1SUM

This converts 1 usage of this option to the non-SPL form, since there is
no SPL_CMD_SHA1SUM defined in Kconfig

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/common/hash.c b/common/hash.c
index 2ce79b9..9a52d60 100644
--- a/common/hash.c
+++ b/common/hash.c
@@ -326,7 +326,7 @@
 };
 
 /* Try to minimize code size for boards that don't want much hashing */
-#if CONFIG_IS_ENABLED(SHA256) || CONFIG_IS_ENABLED(CMD_SHA1SUM) || \
+#if CONFIG_IS_ENABLED(SHA256) || IS_ENABLED(CONFIG_CMD_SHA1SUM) || \
 	CONFIG_IS_ENABLED(CRC32_VERIFY) || IS_ENABLED(CONFIG_CMD_HASH) || \
 	CONFIG_IS_ENABLED(SHA384) || CONFIG_IS_ENABLED(SHA512)
 #define multi_hash()	1