mesa: allow multi-slot program parameters

also the removed comment was incorrect.

Acked-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6946>

src/mesa/program/prog_parameter.c

@@ -261,7 +261,7 @@ _mesa_add_parameter(struct gl_program_parameter_list *paramList,
                     const gl_state_index16 state[STATE_LENGTH],
                     bool pad_and_align)
 {
-   assert(0 < size && size <=4);
+   assert(0 < size);
    const GLuint oldNum = paramList->NumParameters;
    unsigned oldValNum = paramList->NumParameterValues;
    const unsigned padded_size = pad_and_align ? align(size, 4) : size;
@@ -271,7 +271,7 @@ _mesa_add_parameter(struct gl_program_parameter_list *paramList,
    else if (_mesa_gl_datatype_is_64bit(datatype))
       oldValNum = align(oldValNum, 2); /* pad start to 64-bit */
 
-   _mesa_reserve_parameter_storage(paramList, 1, 1);
+   _mesa_reserve_parameter_storage(paramList, 1, DIV_ROUND_UP(padded_size, 4));
 
    if (!paramList->Parameters || !paramList->ParameterValueOffset ||
        !paramList->ParameterValues) {
@@ -299,7 +299,8 @@ _mesa_add_parameter(struct gl_program_parameter_list *paramList,
    paramList->ParameterValueOffset[oldNum] = oldValNum;
    if (values) {
       if (size >= 4) {
-         COPY_4V(paramList->ParameterValues + oldValNum, values);
+         memcpy(paramList->ParameterValues + oldValNum, values,
+                size * sizeof(values[0]));
       } else {
          /* copy 1, 2 or 3 values */
          assert(size < 4);

src/mesa/program/prog_parameter.h

@@ -107,7 +107,6 @@ struct gl_program_parameter
     * Number of components (1..4), or more.
     * If the number of components is greater than 4,
     * this parameter is part of a larger uniform like a GLSL matrix or array.
-    * The next program parameter's Size will be Size-4 of this parameter.
     */
    GLushort Size;
    /**