Ton of unnecessary drawcalls produced by r_consoleFont remap

[JKSunny]

As explained on discord already, when I did modular renderer + vulkan port.
I noticed something off using renderdoc,.

ISSUE:

Just rendering main menu + open console with minimal content already results in over 450 drawcalls.

vulkan-renderdoc.mp4

 
 
 
Nativly it should merge matching shaders and do it in about 30 drawcalls, this is huge difference.

expected-behaivior.mp4

 
I have checked this on Vanilla renderer, with the same result.

r_consoleFont being set higher then "0" is what is causing this, Which seem to default to "1".
So for most people it is adding overhead.

vanilla.mp4

REASON:

r_consoleFont is using shader remapping here.
https://github.com/JKSunny/jk2mv/blob/5e9a273895e73342e03221df546a7c6d59812ea4/src/renderer/tr_cmds.cpp#L393-L405

	//
	// console font stuff
	//
	if ( r_consoleFont->modified ) {
		r_consoleFont->modified = qfalse;

		if ( r_consoleFont->integer == 1 )
			R_RemapShader("gfx/2d/charsgrid_med", "gfx/2d/code_new_roman", 0);
		else if ( r_consoleFont->integer == 2 )
			R_RemapShader("gfx/2d/charsgrid_med", "gfx/2d/mplus_1m_bold", 0);
		else
			R_RemapShader("gfx/2d/charsgrid_med", "gfx/2d/charsgrid_med", 0);
	}

setting sh->remappedShader pointer.

Then when a character or symbol is processsed for rendering, it starts here:
https://github.com/JKSunny/jk2mv/blob/master/src/renderer/tr_backend.cpp#L885-L892

	shader = cmd->shader;
	
	// info
	// shader == the orignal shader
	// tess.shader == sh->remappedShader. set in tr_shade.cpp:RB_BeginSurface( )
	// making this always fire, causing a new drawcall 
	
	if ( shader != tess.shader ) {   
		if ( tess.numIndexes ) {
			RB_EndSurface();
		}
		backEnd.currentEntity = &backEnd.entity2D;
		RB_BeginSurface( shader, 0 );
	}

For my vulkan port I did ad a quick hotfix, more or less to illustrate the problem.

        // from:
        if ( shader != tess.shader ) {   
        
        // to:
	if ( shader != tess.shader && 
		 !( tess.shader && shader->remappedShader && shader->remappedShader == tess.shader ) ) 

However I think this should be done in an earlier stage.
Likely not using "R_RemapShader" at all.

Anyway, I think this should be enough to picture this.