generalzzd fix ios compling error (#2288)

Co-authored-by: Zidi <[email protected]>

src/renderer_gl.h

@@ -620,6 +620,10 @@ typedef uint64_t GLuint64;
 #	define GL_MAX_SAMPLES 0x8D57
 #endif // GL_MAX_SAMPLES
 
+#ifndef GL_MAX_SAMPLES_IMG 
+#   define GL_MAX_SAMPLES_IMG 0x9135
+#endif // GL_MAX_SAMPLES_IMG
+
 #ifndef GL_MAX_COLOR_ATTACHMENTS
 #	define GL_MAX_COLOR_ATTACHMENTS 0x8CDF
 #endif // GL_MAX_COLOR_ATTACHMENTS