fix should_stagger_image_set due to previous merge commit

Author: rohvani

indra/llrender/llimagegl.cpp

@@ -1051,7 +1051,9 @@ U32 type_width_from_pixtype(U32 pixtype)
 
 bool should_stagger_image_set(bool compressed)
 {
-#if LL_DARWIN || LL_LINUX
+#if LL_LINUX
+    return false;
+#elif LL_DARWIN
     return !compressed && on_main_thread() && gGLManager.mIsAMD;
 #else
     // glTexSubImage2D doesn't work with compressed textures on select tested Nvidia GPUs on Windows 10 -Cosmic,2023-03-08