fatfs: Fix some memory leak issues by coverity static analyzer.

components/fatfs/src/ff.c

@@ -5555,7 +5555,12 @@ FRESULT f_mkfs (
 		sz_buf = len / ss;		/* Size of working buffer (sector) */
 		szb_buf = sz_buf * ss;	/* Size of working buffer (byte) */
 	}
-	if (!buf || sz_buf == 0) return FR_NOT_ENOUGH_CORE;
+	if (!buf || sz_buf == 0) {
+#if FF_USE_LFN == 3
+		ff_memfree(buf);
+#endif
+		return FR_NOT_ENOUGH_CORE;
+	}
 
 	/* Determine where the volume to be located (b_vol, sz_vol) */
 	if (FF_MULTI_PARTITION && part != 0) {

components/fatfs/src/vfs_fat.c

@@ -557,12 +557,12 @@ static int vfs_fat_link(void* ctx, const char* n1, const char* n2)
     }
 fail3:
     f_close(pf2);
-    free(pf2);
 fail2:
     f_close(pf1);
-    free(pf1);
 fail1:
     free(buf);
+    free(pf2);
+    free(pf1);
     if (res != FR_OK) {
         ESP_LOGD(TAG, "%s: fresult=%d", __func__, res);
         errno = fresult_to_errno(res);