target/ppc: Reduce the size of ppc_spr_t

We elide values when registering sprs, we might as well
save space in the array as well.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210501022923.1179736-3-richard.henderson@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

target/ppc/cpu.h

@@ -192,17 +192,21 @@ typedef struct ppc_hash_pte64 ppc_hash_pte64_t;
 
 /* SPR access micro-ops generations callbacks */
 struct ppc_spr_t {
+    const char *name;
+    target_ulong default_value;
+#ifndef CONFIG_USER_ONLY
+    unsigned int gdb_id;
+#endif
+#ifdef CONFIG_TCG
     void (*uea_read)(DisasContext *ctx, int gpr_num, int spr_num);
     void (*uea_write)(DisasContext *ctx, int spr_num, int gpr_num);
-#if !defined(CONFIG_USER_ONLY)
+# ifndef CONFIG_USER_ONLY
     void (*oea_read)(DisasContext *ctx, int gpr_num, int spr_num);
     void (*oea_write)(DisasContext *ctx, int spr_num, int gpr_num);
     void (*hea_read)(DisasContext *ctx, int gpr_num, int spr_num);
     void (*hea_write)(DisasContext *ctx, int spr_num, int gpr_num);
-    unsigned int gdb_id;
+# endif
 #endif
-    const char *name;
-    target_ulong default_value;
 #ifdef CONFIG_KVM
     /*
      * We (ab)use the fact that all the SPRs will have ids for the