Fix loading of png images in custom themes

Change-Id: I7eebc474c025eda534adb04d061795623ebecdda
diff --git a/minuitwrp/resources.c b/minuitwrp/resources.c
index 6f6d13b..bb30147 100644
--- a/minuitwrp/resources.c
+++ b/minuitwrp/resources.c
@@ -63,8 +63,11 @@
     resPath[sizeof(resPath)-1] = '\0';
     FILE* fp = fopen(resPath, "rb");
     if (fp == NULL) {
-        result = -1;
-        goto exit;
+        fp = fopen(name, "rb");
+        if (fp == NULL) {
+            result = -1;
+            goto exit;
+        }
     }
 
     size_t bytesRead = fread(header, 1, sizeof(header), fp);