st/mesa: drop u_simple_shaders.h include where not used.

These functions aren't used in here anymore.

Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/29793>

src/mesa/state_tracker/st_atom_shader.c

@@ -46,7 +46,6 @@
 
 #include "pipe/p_context.h"
 #include "pipe/p_shader_tokens.h"
-#include "util/u_simple_shaders.h"
 #include "cso_cache/cso_context.h"
 #include "util/u_debug.h"
 

src/mesa/state_tracker/st_cb_drawpixels.c

@@ -70,7 +70,6 @@
 #include "util/format/u_format.h"
 #include "util/u_inlines.h"
 #include "util/u_math.h"
-#include "util/u_simple_shaders.h"
 #include "util/u_tile.h"
 #include "cso_cache/cso_context.h"
 

src/mesa/state_tracker/st_cb_drawtex.c

@@ -32,7 +32,6 @@
 #include "util/u_inlines.h"
 #include "pipe/p_shader_tokens.h"
 #include "util/u_draw_quad.h"
-#include "util/u_simple_shaders.h"
 #include "util/u_upload_mgr.h"
 
 #include "cso_cache/cso_context.h"

src/mesa/state_tracker/st_cb_texture.c

@@ -82,7 +82,6 @@
 #include "util/u_math.h"
 #include "util/box.h"
 #include "util/u_memory.h"
-#include "util/u_simple_shaders.h"
 #include "cso_cache/cso_context.h"
 
 #define DBG if (0) printf