glsl: Modify the #includes in the DXT5 shaders

1. Drop the commented out includes. Shader caching is disabled if those
   are found.

2. Replace the active includes with "%s". Later on, we'll construct the
   final strings with vasprintf. One downside to doing this is that the
   glsl file extensions are no longer true. These files are now
   templates.

Reviewed-by: Tapani Pälli <tapani.palli@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19827>

src/compiler/glsl/bc1.glsl

@@ -31,9 +31,7 @@
 	#define const
 #endif
 
-// #include "/media/matias/Datos/SyntaxHighlightingMisc.h"
-
-#include "CrossPlatformSettings_piece_all.glsl"
+%s // include "CrossPlatformSettings_piece_all.glsl"
 
 #define FLT_MAX 340282346638528859811704183484516925440.0f
 

src/compiler/glsl/bc4.glsl

@@ -33,9 +33,7 @@
 
 #define __sharedOnlyBarrier memoryBarrierShared();barrier();
 
-// #include "/media/matias/Datos/SyntaxHighlightingMisc.h"
-
-#include "CrossPlatformSettings_piece_all.glsl"
+%s // include "CrossPlatformSettings_piece_all.glsl"
 
 shared float2 g_minMaxValues[4u * 4u * 4u];
 shared uint2 g_mask[4u * 4u];

src/compiler/glsl/etc2_rgba_stitch.glsl

@@ -27,9 +27,7 @@
 
 #version 310 es
 
-// #include "/media/matias/Datos/SyntaxHighlightingMisc.h"
-
-#include "CrossPlatformSettings_piece_all.glsl"
+%s // include "CrossPlatformSettings_piece_all.glsl"
 
 layout( local_size_x = 8,  //
 		local_size_y = 8,  //