patch: Don't spam the log when no patch file was loaded

When invoking QDL in a way that doesn't involve patching (e.g. by
invoking a read) the "0 patches applied" is annoying and can be
confusing.

Make this statement conditional on patch files actually having been
loaded.

Signed-off-by: Bjorn Andersson <[email protected]>

Author: quic-bjorande

patch.c

@@ -14,6 +14,7 @@
 #include "qdl.h"
 
 static struct list_head patches = LIST_INIT(patches);
+static bool patches_loaded;
 
 int patch_load(const char *patch_file)
 {
@@ -63,6 +64,8 @@ int patch_load(const char *patch_file)
 
 	xmlFreeDoc(doc);
 
+	patches_loaded = true;
+
 	return 0;
 }
 
@@ -73,6 +76,9 @@ int patch_execute(struct qdl_device *qdl, int (*apply)(struct qdl_device *qdl, s
 	unsigned int idx = 0;
 	int ret;
 
+	if (!patches_loaded)
+		return 0;
+
 	list_for_each_entry(patch, &patches, node) {
 		if (!strcmp(patch->filename, "DISK"))
 			count++;