renderer: disable ARB_shader_draw_parameters on GLSL 1.20

[illwieckz]

Disable ARB_shader_draw_parameters on GLSL 1.20.

Extracted from:

• renderer: add non-bitwise alternative for u_Color and u_ColorModulateColorGen #1570

Fixes #1575:

• Some material shader code is built even when glConfig2.usingMaterialSystem is false #1575

[VReaperV]

How about just disabling the extension on version 120? I think that would be a cleaner approach.

[illwieckz]

How about just disabling the extension on version 120? I think that would be a cleaner approach.

That was my first implementation but then I thought this would be better instead. 🤭️

I reverted to disabling the extension on version 120.

[VReaperV]

Non-blocking, might want to name all of these as *ShaderDrawParameters for consistency (and with camelCase for variables).

LGTM.

[illwieckz]

Non-blocking, might want to name all of these as *ShaderDrawParameters for consistency (and with camelCase for variables).

Good catch, fixed.