math: remove unused defines

Since libmesa_classic got removed, we no longer have the assembly
sources that used these defines, so let's get rid of them.

Reviewed-by: Yonggang Luo <luoyonggang@gmail.com>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24003>

src/mesa/math/m_matrix.c

@@ -953,9 +953,6 @@ _math_matrix_viewport(GLmatrix *m, const float scale[3],
 void
 _math_matrix_set_identity( GLmatrix *mat )
 {
-   STATIC_ASSERT(MATRIX_M == offsetof(GLmatrix, m));
-   STATIC_ASSERT(MATRIX_INV == offsetof(GLmatrix, inv));
-
    memcpy( mat->m, Identity, sizeof(Identity) );
    memcpy( mat->inv, Identity, sizeof(Identity) );
 

src/mesa/math/m_matrix.h

@@ -54,13 +54,6 @@ extern "C" {
 #define MAT_TZ 14
 /*@}*/
 
-/**
- * If you add a new field, please add it to the STATIC_ASSERTs in
- * _math_matrix_set_identity().
- */
-#define MATRIX_M   0
-#define MATRIX_INV (MATRIX_M + 16 * 4)
-
 /**
  * Different kinds of 4x4 transformation matrices.
  * We use these to select specific optimized vertex transformation routines.