### Godot version

4.0b17

### System information

macOS 13.2

### Issue description

The shader function fma, used by the visual shader UVFunc node generated code:
```
// UVFunc:5
vec2 n_in5p1 = vec2(6.00000, 6.00000);
vec2 n_in5p2 = vec2(0.50000, 0.50000);
vec2 n_out5p0 = fma((UV - n_in5p2), n_in5p1, n_in5p2);
```
Does not seem to be defined in the Compatibility renderer, causing shader compilation to fail if it's used with a lot of errors and debug output (10000+ messages as it prints out a lot of engine shader code?). Ending with the relevant errors:
 ```
drivers/gles3/shader_gles3.cpp:242 - SceneShaderGLES3: Fragment shader compilation failed:
  ERROR: 0:928: Invalid call of undeclared identifier 'fma'
  ERROR: 0:930: Use of undeclared identifier 'm_n_out5p0'
  
  drivers/gles3/shader_gles3.cpp:342 - Method/function failed.
```

Simple shader using fma in Mobile:
![Screenshot 2023-02-08 at 09 52 38](https://user-images.githubusercontent.com/17763524/217483066-fe0feab7-72c4-4db7-a44e-041a1ad93f25.jpg)

Switch to Compatibility renderer:
![Screenshot 2023-02-08 at 09 53 27](https://user-images.githubusercontent.com/17763524/217483149-4fdef308-67cf-40d2-8d4a-d72dc7c85e70.jpg)



### Steps to reproduce

- Start a project in Mobile
- Make a shader where you use the fma function, for example the shader below in the reproduction field. Or a visual shader using the UVFunc node.
- Assign the shader to a shader material and apply this to a visible mesh, observe it renders
- Switch project to Compatibility renderer
- See errors and failed shader compilation

### Minimal reproduction project

Minimal test shader, use in Compatibility renderer:

```
shader_type spatial;

void fragment() {
	vec2 n_in5p1 = vec2(6.00000, 6.00000);
	vec2 n_in5p2 = vec2(0.50000, 0.50000);
	vec2 n_out5p0 = fma((UV - n_in5p2), n_in5p1, n_in5p2);

	ALBEDO = vec3(1,0,0);
}

```
BIND_ENUM_CONSTANT(FUNC_LOG2);
	BIND_ENUM_CONSTANT(FUNC_RADIANS);
	BIND_ENUM_CONSTANT(FUNC_RECIPROCAL);
	BIND_ENUM_CONSTANT(FUNC_ROUNDEVEN);
	BIND_ENUM_CONSTANT(FUNC_TRUNC);
	BIND_ENUM_CONSTANT(FUNC_ONEMINUS);
	BIND_ENUM_CONSTANT(FUNC_MAX);
}
VisualShaderNodeFloatFunc::VisualShaderNodeFloatFunc() {
	set_input_port_default_value(0, 0.0);
}
String VisualShaderNodeIntFunc::get_caption() const {
	return "IntFunc";
}
int VisualShaderNodeIntFunc::get_input_port_count() const {
	return 1;
}
VisualShaderNodeIntFunc::PortType VisualShaderNodeIntFunc::get_input_port_type(int p_port) const {
	return PORT_TYPE_SCALAR_INT;
}
String VisualShaderNodeIntFunc::get_input_port_name(int p_port) const {
	return "";
}
int VisualShaderNodeIntFunc::get_output_port_count() const {
	return 1;
}
VisualShaderNodeIntFunc::PortType VisualShaderNodeIntFunc::get_output_port_type(int p_port) const {
	return PORT_TYPE_SCALAR_INT;
}
String VisualShaderNodeIntFunc::get_output_port_name(int p_port) const {