internal/gl: use libGLESv2.so.2 for Unix platforms

The unprefixed library names are for development, and Android.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

internal/gl/gl_unix.go

@@ -561,8 +561,10 @@ func (f *Functions) load(forceES bool) error {
 		libNames = []string{"libGLESv2.dylib"}
 	case runtime.GOOS == "ios":
 		libNames = []string{"/System/Library/Frameworks/OpenGLES.framework/OpenGLES"}
-	default:
+	case runtime.GOOS == "android":
 		libNames = []string{"libGLESv2.so", "libGLESv3.so"}
+	default:
+		libNames = []string{"libGLESv2.so.2"}
 	}
 	for _, lib := range libNames {
 		if h := dlopen(lib); h != nil {