FFvaluestore: fix UB reported by clang

Author: CarterLi

src/util/FFvaluestore.c

@@ -2,7 +2,7 @@
 
 #include <string.h>
 
-typedef char KeyType[33]; //32 byte key + \0
+typedef char KeyType[32]; //31 byte key + \0
 
 void ffValuestoreInit(FFvaluestore* vs, uint32_t valueSize)
 {

src/util/FFvaluestore.h

@@ -10,7 +10,7 @@ typedef FFlist FFvaluestore;
 
 void ffValuestoreInit(FFvaluestore* vs, uint32_t valueSize);
 FF_C_NODISCARD void* ffValuestoreGet(FFvaluestore* vs, const char* key);
-void* ffValuestoreSet(FFvaluestore* vs, const char* key, bool* created); //created may be NULL
+FF_C_NODISCARD void* ffValuestoreSet(FFvaluestore* vs, const char* key, bool* created); //created may be NULL
 void ffValuestoreDestroy(FFvaluestore* vs);
 
 #endif