[Web] Disable thorvg threads on the Web

They're of little help, and just adds to the possibility of causing
deadlocks.

thirdparty/thorvg/inc/config.h

@@ -5,7 +5,9 @@
 #define THORVG_SVG_LOADER_SUPPORT
 #define THORVG_PNG_LOADER_SUPPORT
 #define THORVG_JPG_LOADER_SUPPORT
+#ifndef WEB_ENABLED
 #define THORVG_THREAD_SUPPORT
+#endif
 
 // Added conditionally if webp module is enabled.
 //#define THORVG_WEBP_LOADER_SUPPORT

thirdparty/thorvg/update-thorvg.sh

@@ -38,7 +38,9 @@ cat << EOF > ../inc/config.h
 #define THORVG_SVG_LOADER_SUPPORT
 #define THORVG_PNG_LOADER_SUPPORT
 #define THORVG_JPG_LOADER_SUPPORT
+#ifndef WEB_ENABLED
 #define THORVG_THREAD_SUPPORT
+#endif
 
 // Added conditionally if webp module is enabled.
 //#define THORVG_WEBP_LOADER_SUPPORT