Remove unused imports.

PiperOrigin-RevId: 461829404
Change-Id: I9ae44085af211013ed2b677b7d3a545ccec34605

src/engine/engine_core_constraint.c

@@ -27,7 +27,6 @@
 #include "engine/engine_util_blas.h"
 #include "engine/engine_util_errmem.h"
 #include "engine/engine_util_misc.h"
-#include "engine/engine_util_solve.h"
 #include "engine/engine_util_sparse.h"
 #include "engine/engine_util_spatial.h"
 

src/engine/engine_util_sparse.c

@@ -21,7 +21,6 @@
 #include "engine/engine_io.h"
 #include "engine/engine_macro.h"
 #include "engine/engine_util_blas.h"
-#include "engine/engine_util_errmem.h"
 
 #ifdef mjUSEPLATFORMSIMD
   #if defined(__AVX__) && defined(mjUSEDOUBLE)

src/user/user_util.cc

@@ -20,10 +20,7 @@
 #include <limits>
 #include <string>
 
-#include <mujoco/mjmodel.h>
-#include "engine/engine_file.h"
 #include "engine/engine_macro.h"
-#include "engine/engine_util_errmem.h"
 
 using std::isnan;
 using std::string;