ppc: POWER7 has lq/stq instructions and stq need to check ISA version

The PPC_64BX instruction flag is used for a couple of newer instructions currently on POWER8 but our implementation for them works for POWER7 too (and already does the proper checking of what is permitted) with one exception: stq needs to check the ISA version.

This fixes the latter and add the instructions to POWER7

---
 target-ppc/translate.c      | 5 ++++-
 target-ppc/translate_init.c | 2 +-

 2 files changed, 5 insertions(+), 2 deletions(-)

index ab5862f..b34289f 100644
@@ -3047,10 +3047,13 @@ static void gen_std(DisasContext *ctx)

     rs = rS(ctx->opcode);
     if ((ctx->opcode & 0x3) == 0x2) { /* stq */
-
         bool legal_in_user_mode = (ctx->insns_flags2 & PPC2_LSQ_ISA207) != 0; bool le_is_supported = (ctx->insns_flags2 & PPC2_LSQ_ISA207) != 0;
+        if (!(ctx->insns_flags & PPC_64BX)) {
+            gen_inval_exception(ctx, POWERPC_EXCP_INVAL_INVAL); +        }
+
         if (!legal_in_user_mode && ctx->pr) { gen_inval_exception(ctx, POWERPC_EXCP_PRIV_OPC); return;

index ad6f2f3..a1db500 100644
@@ -8377,7 +8377,7 @@ POWERPC_FAMILY(POWER7)(ObjectClass *oc, void *data)

                        PPC_CACHE | PPC_CACHE_ICBI | PPC_CACHE_DCBZ | PPC_MEM_SYNC | PPC_MEM_EIEIO | PPC_MEM_TLBIE | PPC_MEM_TLBSYNC |

-                       PPC_64B | PPC_64H | PPC_ALTIVEC |
+                       PPC_64B | PPC_64H | PPC_64BX | PPC_ALTIVEC |

                        PPC_SEGMENT_64B | PPC_SLBI | PPC_POPCNTB | PPC_POPCNTWD; pcc->insns_flags2 = PPC2_VSX | PPC2_DFP | PPC2_DBRX | PPC2_ISA205 |