ir3/legalize: Use define for register size

This was introduced in a previous commit

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/22075>

src/freedreno/ir3/ir3.h

@@ -1379,17 +1379,6 @@ writes_pred(struct ir3_instruction *instr)
    return false;
 }
 
-/* Is it something other than a normal register. Shared regs, p0, and a0/a1
- * are considered special here. Special registers are always accessed with one
- * size and never alias normal registers, even though a naive calculation
- * would sometimes make it seem like e.g. r30.z aliases a0.x.
- */
-static inline bool
-is_reg_special(const struct ir3_register *reg)
-{
-   return (reg->flags & IR3_REG_SHARED) || !is_reg_gpr(reg);
-}
-
 /* r0.x - r47.w are "normal" registers. r48.x - r55.w are shared registers.
  * Everything above those are non-GPR registers like a0.x and p0.x that aren't
  * assigned by RA.

src/freedreno/ir3/ir3_delay.c

@@ -124,14 +124,11 @@ ir3_delayslots_with_repeat(struct ir3_instruction *assigner,
    if (assigner->opc == OPC_MOVMSK)
       return delay;
 
-   bool mismatched_half =
-      (src->flags & IR3_REG_HALF) != (dst->flags & IR3_REG_HALF);
-
    /* TODO: Handle the combination of (rpt) and different component sizes
     * better like below. This complicates things significantly because the
     * components don't line up.
     */
-   if (mismatched_half)
+   if ((src->flags & IR3_REG_HALF) != (dst->flags & IR3_REG_HALF))
       return delay;
 
    /* If an instruction has a (rpt), then it acts as a sequence of

src/freedreno/ir3/ir3_legalize.c

@@ -55,8 +55,8 @@ struct ir3_legalize_ctx {
 };
 
 struct ir3_nop_state {
-   unsigned full_ready[4 * 48];
-   unsigned half_ready[4 * 48];
+   unsigned full_ready[GPR_REG_SIZE];
+   unsigned half_ready[GPR_REG_SIZE];
 };
 
 struct ir3_legalize_state {